CBSE-i CLASS IX

Shiksha Kendra, 2, Community Centre, Preet Vihar, Delhi-110 092 India

UNIT-2

SCIENCESCIENCE

F O R C E A N D M O T I O NM AT E R I A L S

C E L L D I V I S I O N

The Curriculum initiated by Central Board of Secondary Education -International (CBSE-i) is

a progressive step in making the educational content and methodology more sensitive and

responsive to the global needs. It signifies the emergence of a fresh thought process in

imparting a curriculum which would restore the independence of the learner to pursue the

learning process in harmony with the existing personal, social and cultural ethos.

The Central Board of Secondary Education, with about 11000 schools affiliated to it and with

over 130 schools situated in more than 20 countries has been catering to the academic needs of

the learners worldwide. The Board has always been conscious of the varying needs of the

learners in countries abroad and has been working towards contextualizing certain elements

of the learning process to the physical, geographical, social and cultural environment in which

they are engaged. The International Curriculum being designed by CBSE-i , has been

visualized and developed with these requirements in view.

The nucleus of the entire process of constructing the curricular structure is the learner. The

objective of the curriculum is to nurture the independence of the learner, given the fact that

every learner is unique. The learner has to understand, appreciate, protect and build on

values, beliefs and traditional wisdom, making necessary modifications, improvisations and

additions wherever and whenever necessary.

The recent scientific and technological advances have thrown open the gateways of

knowledge at an astonishing pace. The speed and methods of assimilating knowledge have

put forth many challenges to the educators, forcing them to rethink their approaches for

knowledge processing by their learners. In this context, it has become imperative for them to

incorporate those skills which will enable the young learners to become 'life long learners'. The

ability to stay current, to upgrade skills with emerging technologies, to understand the

nuances involved in change management and the relevant life skills have to be a part of the

learning domains of the global learners. The CBSE-i curriculum has taken cognizance of these

requirements.

The CBSE-i aims to carry forward the basic strength of the Indian system of education. While

promoting critical and creative thinking skills, effective communication skills, interpersonal

and collaborative skills along with information and media skills. There is an inbuilt flexibility

as it provides a foundation and an extension curriculum in all subject areas to cater to the

different pace of learners.

PrefacePreface

i

The CBSE-i plans to introduce the curriculum in a phased manner at different levels in schools

affiliated to CBSE at the international level and subsequently, if desirable, to introduce it to

other affiliated schools who are able to meet the requirements of this curriculum. The focus is

to ensure that the learner is stress-free and yet stays committed to active learning. The learner

would be evaluated on a continuous and comprehensive basis consequent to the mutual

interactions between the teacher and the learner and the learner. There are some non-

evaluative components in the curriculum which would be commented upon by the teachers

and the school. The objective of this part or the core of the curriculum is to scaffold the learning

experiences and to relate tacit knowledge with formal knowledge. This would involve trans-

disciplinary linkages that would form the core of the learning process. Perspectives, SEWA

(Social Empowerment through Work and Action), Life Skills and Research would be the

constituents of this 'Core'. The Core skills are the most significant aspects of a learner's holistic

growth and his/her learning curve.

The international curriculum has been designed keeping in view the foundations of the

National Curricular Framework (NCF 2005) and the experience gathered by the Board over

the last seven decades in imparting effective learning to millions of learners, many of whom

are now global citizens.

The Board does not interpret this development as an alternative to other curricula existing at

the international level, but as an exercise in providing the much needed Indian leadership for

global education at the school level. The international curriculum would evolve on its own-

building on learning experiences inside the classroom over a period of time. The Board while

addressing the issues of empowerment with the help of the schools administering this system

strongly recommends that practicing teachers become skillful learners on their own and also

transfer their learning experiences to their peers through the interactive platforms to be

provided by the Board.

I profusely thank Shri G. Balasubramanian, former Director (Academics),CBSE, Ms. Abha

Adams and her team and Dr. Sadhana Parashar, Head (Innovations and Research) CBSE

alongwith other Education Officers involved in the development and implementation of this

material.

The CBSE-i website being launched will enable all stakeholders involved in this initiative to

participate through the discussion forums provided on the portal. Any further suggestions for

modifying or improving any part of this document are welcome.

Vineet Joshi

Chairman

CBSE

Advisory

Conceptual Framework

Ideators

Material Production Groups : Classes IX - X

Shri Vineet Joshi, Chairman & Secretary, CBSE

Smt. Chitralekha Gurumurthy, Director (Academics),CBSE

Dr. Sadhana Parashar, Head (Innovations & Research),CBSE

Shri G. Balasubramanian, Former Director (Academics), CBSE

Ms. Abha Adams, Consultant, Step-by-Step School, Noida

Dr. Sadhana Parashar, Head (Innovations & Research),CBSE

Dr. Indu Khetrapal Ms. Rupa Chakravarty

Dr. N. K. Sehga Ms. Jaishree Srivastava

Ms. Anita Sharma Dr. Anju Srivastava

Dr. Uma Chaudhary Dr. Kamla Menon

Ms. Meenu Goswami Ms. Anuradha Sen

Ms. Geeta Varshney Dr. Rajesh Hassija

Ms. Urmila Chowdhary Ms. Amita Mishra

Ms. Aditi Misra

Dr. K.P. Chinda Ms. Charu Maini

Mr. J.C. Nijhawan Ms. S. Anjum

Ms. Rashmi Kathuria Ms. Meenambika Menon

Ms. Reemu Verma Ms. Novita Chopra

Ms. Nita Rastogi

Ms. Pooja Sareen

Ms. Jayshree Srivastava Ms. Sarita Manuja

Mrs. M. Bose Ms. Gayatri Khanna

Ms. A. Venkatachalam Ms. Renu Anand

Ms. Smita Bhattacharya Ms. P. Rajeshwary

Mrs. Neelima Sharma

Ms. Neha Sharma

Mathematics : Science :

History : English :

AcknowledgementsAcknowledgements

Ms. Deepa Kapoor Ms Sharmila Bakshi

Ms. Bharti Dave Ms. Srilekha

Ms. Bhagirathi Ms. Archana Soni

Ms. Mridula Pant

Sh. Pankaj Bhanwani

Ms. Savinder Kaur Rooprai

Ms. Nandita Pal

Ms. Deepti Verma

Ms. Seema Choudhary

Ms. Monika Thakur

Mr. Bijo Thomas

Ms Ruba Chakravarty

Ms. Guneet Ohri

Ms. Dipinder Kaur

Ms. Sonia Jain

Ms. Seema Rawat

Dr. Meena Dhami

Mrs. N Vidya

Mrs. Sugandh Sharma, Education Officer (Com.)

Dr. Srijata Das, Education Officer (Science & Maths)

Sh. R. P. Sharma, Consultant

Shri Al Hilal Ahmed, Asstt. Education Officer

Geography : Poltical Science :

Economics :

Material Production Groups : Classes I - V

Material Production Groups : Classes VI - VIII

Co-ordinators :

Preface

1 Aims and Objectives of Learning Science 1

2 Enquiry Based Learning – Core Premises 2

3 Enquiry Based Learning in Science – Few Examples 3

4 Syllabus Coverage (Physics) 4

5 Scope Document 5

6 Lesson template 9

7 Activity Sheets 11

8.

9. Annexures (1 to 7) 36

10.

Acknowledgements

Student and Teacher Support Materials 28

Syllabus Coverage (Chemistry) 46

11. Scope Document 47

12. Rubrics Of Assessment For Learning 50

13. Lesson template for UNIT 2:Materials: Section 1 52

14. Lesson template for UNIT 2:Materials: Section 2 54

15. Student and Teacher Support Materials (1-29) 56

16. Syllabus Coverage (Biology) 113

17. Scope Document 114

18. Lesson Template 118

19. Student and Teacher Support Materials 121

20. Assessment Rubric 141

Page No.

CONTENTS

1SCIENCE UNIT - 2

The Aims of the Science Curriculum are to

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Portray Science as a set of ideas and processes

Help students develop a coherent knowledge and understanding of the

environment around them

Promote Science as an activity that can be carried out by all people as a part of their

daily lives and develop scientific attitudes

Help students appreciate the implications of Scientific study and its limitations

Encourage students to use the Scientific method and scientific skills to evaluate

ideas and make choices/decisions

Develop an understanding about the evolving nature of science

Assist students to understand the need to make responsible decisions on the use of

Science and technology and to consider its impact on the environment

Nurture scientific talent

Develop students’ interest and knowledge of Scientific ideas for use in choosing

careers and to make a strong foundation for further studies

To develop curiosity and give students an opportunity to explore the magic of

Science

1 Aims and Objectives of teaching Science

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2 ENQUIRY BASED LEARNING – CORE PREMISES

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Learning should be based around the students’ questions.

Pedagogy requires students to work together to solve problems rather than receiving

direct instructions from the teacher.

Teacher is a facilitator in learning rather than acting as a vessel of knowledge.

Teacher’s role is to help the student in the process of discovering knowledge themselves.

Students use their background knowledge of facts, concepts and principles along with

process skills to construct new knowledge (Constructivist Approach).Knowledge is built

in a stepwise fashion.

Students are assessed by how well they develop experimental and analytical skills rather

than how much knowledge they possess.

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Students develop a method to find which antacid tablets are the best at neutralizing

acids.

Students learn about inertia and movement by studying what affect rolling of marbles

have on different surfaces .

Students work in groups to build bridges to hold marble weights. By doing so they

discover how to build strong bridges.

Students learn about buoyancy and laws of floatation by studying what affect dipping of

different bodies in different liquids has on their apparent weight.

3 Enquiry Based Learning In Science - Few Examples

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4 Syllabus Coverage (Physics)

Force and motionForce definition and types of forces

Vector addition and balanced and unbalanced forces

Newton’s laws – inertia, momentum, action, reaction etc.

Conservation of momentum and the third law

Collisions

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5 Scope Document

This unit is meant to develop an understanding of forces and their nature and to help

studentsinvestigate and describe their ideas about some everyday examples of physical

phenomena, e.g., pushes and pulls, magnetism etc. They observe and explore trends and

relationships found in easily observable physical Phenomena and describe, in simple terms,

how items of everyday technology work and affect our lives.

At the end of this unit students should be able to

Define and describe a force

Explain the action of a force

Identify and describe different kinds of forces

Recall Newton as a unit for measuring force

Explain how forces can be measured and perform experiments on springs

Explain experimental results on spring extension and interpret the results

Describe inertia as a property of all masses

State and describe Newton’s laws of motion

Recall and use the laws to explain observable phenomena

Recall and use F = ma

Explain how force causes acceleration and is hence required to make an object move

in a circle

Elementary ideas of centripetal force (without naming it).

Describe momentum and explain its relevance to the second law

State and explain the law of conservation of momentum and its application to the

third law

Apply the laws to everyday life situations

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Learning OutComes - Foundation

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Learning outcomes – Extension

Suggested activities / processes

At the end of this unit students should be able to

Explain and understand the difference between scalar and vector addition

Add vectors using different methods – graphical method, triangle and

parallelogram law of addition of vectors

Describe collisions (elementary ideas with many examples), relating them to the

third law

Experiments-

a. Students can watch a video of a football match or any other sport or a potter at work

and answer leading questions on forces. This exercise is used to define a force by

determining what a force can do. Students can be asked to write examples of forces

where they are – changing speed, changing shape, starting, stopping motion etc.

and discuss these with their partners.

b. Students perform a series of experiments on various kinds of forces. These are used

to identify various types of forces- contact and non contact. They go from one

experiment to another and are assisted and supported during class to observe

correctly and record in the correct format. After performing the experiments they

identify the forces, the object on which the force is applied and the action of the

force. This experiment can later be used to identify action – reaction pairs.

c. Students perform or observe experiments which demonstrate the first law – coin on

card etc. and the teacher uses this to explain or introduce the first law.

d. Students can be asked to place an empty bottle on the floor of the car, or bus

whichever way they travel home. They will observe the direction the bottle moves

in and use that to determine when the driver, applied brakes or stepped on the

accelerator. Report their findings in the form of an investigation in their practical

portfolios.

e. Experiments to illustrate the second and the third law. A simulation experiment can

also be planned here. There are many simulations available on collisions and the

second law.

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7SCIENCE UNIT - 2

Problem solving exercises-

Research opportunities

Opportunities

(a). Students should be given pictures of objects with a variety of forces acting on them.

They should identify the various forces and their action. This exercise can be used

twice, once to identify forces and the second time to identify action – reaction pairs.

This exercise can also be used to illustrate vectors and the forces should be drawn as

arrows with their lengths proportional to the size of the force.

(b). Students should solve a variety of problems on F = ma. These can be numerical as

well as applications of the law to explain everyday situations.

(c). Students should be given various scenarios and asked to apply their knowledge of

the three laws to explain these. E.g. Rowing a boat, working of a rocket, walking etc.

(d). Students can watch a video of a billiards game and this can be used to explain

collisions and transfer of momentum. They can also perform simulation

experiments on collision.

(e). Students solve problems on vector addition – only simple problems where either

the vectors are acting along the same line or are perpendicular to each other.

(f). Allow students to investigate designs of various household items like hangers and

see the forces that act on them and comment on the design or on how it can be

improved. Could be in the form of holiday HW or group work.

(g). Describing the pattern of results formed from graphing the effects of applied forces

on a spring.

a) Students can be asked to research on any one type of force and come up with

examples of where we experience them. E.g. magnetic forces are used in motors,

generators, the electric bell etc. These can be displayed in class.

b) Some students may research on Galileo’s experiments and explain to the class how

the findings from those experiments were the same as Newton’s laws. Students

should be provided clear criteria for assessment.

Create opportunities for pupils to draw, and talk about, a collection of common

household appliances to clarify ideas about how they are used

Measuring the strength of a magnet, using numbers of paper clips.

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Comparing pictures or examples of oars for their shape and size.

Plan opportunities for pupils to justify ability to evaluate their work, when the

students make simple weighing devices and compare them with commercial scales

Understanding of the use of an everyday technological item, when the students

explain how wheelchairs assist disabled people to move about and what are the

forces acting on the chair when stationary and when moving.

Designing and making simple rubber-band-force measuring devices and testing

them on a variety of forces.

Measuring the apparent loss of weight of a stone in water to gather information on

Buoyancy.

For developing reporting skills, when the students carry out individual studies of

how various objects work using forces and report back to the class

NCERT Text Book of Science

http://www.bbc.co.uk/scotland/learning/bitesize/standard/physics/

transport/forces_at_work_activity.shtml

http://www.gamequarium.org/dir/SqoolTube_Videos/Science/Forces_and_

Motion/www.tutorvista.com

Art and Design – design of various objects and the force applied on them

Mathematics – problem solving , changing the subject of an equation and graphing

Chemistry – forces in nature – between molecules, atoms – nuclear forces etc..

P.E. –Forces applied and their effects E.g. football, billiards etc.•

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Suggested Links and resources

Animations and Videos

Cross curricular links

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6 Lesson Template

Steps to be followed

Tool/Activity Used Description

1 Topic - Types of Forces Warm Up and testing previous knowledge

Fun Game- Teacher demonstrate and Students identify various types of forces. (Activity-1)

Teacher may start the class with a small demonstration to initiate the investigation.

Building the concept and its application to real life situations

Group Activity- develops multiple intelligence skills. (Activity sheet-2)

Class can be divided into small groups and can be given the activity sheet to identify the forces and draw them.

Formative Assessment Individual Activity- Forces (Activity sheet-3) Extended learning – vector addition Activity sheet – 4 & 5 Revision Exercise – Activity sheet – 6&7

Every student can try and solve the problems individually. See who can solve the maximum?

2. Topic – Newton’s First Law Warming up

Activity 1 & 2 – Teacher demonstrates simple Inertia experiments

Teacher cities examples from daily life and Let every student come out with his/her creative expression. See who makes the most meaningful statements?

PRE-LESSON ACTIVITIES TO BUILD BACKGROUND KNOWLEDGE

Activity 3 Students are asked to summarize the demo and answer questions.

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Lesson development Activity 4& 5 Hand’s on activities for students.

3. Topic – Newton’s Second Law.

Activity 1&2 PRE-LESSON ACTIVITIES TO BUILD BACKGROUND KNOWLEDGE

Teacher demonstrates using student volunteers

Lesson development

4. Topic - Newton’s third law

Activity 3 – Hand's on activity for students

Students are asked to make predictions and then test them

Activity 1& 2 – Pre lesson activity Teacher cities examples from daily life

Developing multiple intelligence skills

Activity 3 & 4 Teacher may ask the students to do hand’s on activity in the classroom.(Instructions attached with pictorial explanation)

Assessment Worksheets Worksheet 1,2 & 3 Catering to formative assessment, developing scientific skills and application to real life situations.

5.Topic – conservation of momentum

Pre lesson activity Teacher gives examples of collision between heavy and light objects and its consequences.

Worksheet 4 ,5, 6 &http://www.ncert.nic.in/book

Designed to develop problem solving skills, Numerical skills and application to daily life situations.

11SCIENCE UNIT - 2

7 ACTIVITY SHEETS (UNIT- FORCE AND MOTION)

Activity Sheet 1.

Procedure:

To test the previous knowledge on forces and its effects.

AIM: To distinguish between contact and non contact forces and understand the effects of

force.

Material Required: Books, magnet, all pins, Plastic straws, woolen cloth piece, tennis ball, wet

clay or plasticine, rubber band, chalk pieces, beaker with water and a rubber cork.

Following the given instructions note down your observations and answer the questions.

1. Six books are kept in two piles. Place the books in one pile.

2. Drag the alpines from a distance with the help of the given magnet.

3. Charge the two plastic straws with the help of the woollen cloth. Try to repel one

straw with the other.

4. Drop the tennis ball from a height

5. Make any shape of your choice out of the wet clay or plasticine.

6. Stretch the rubber band.

7. Break the chalk into small pieces

8. Push the rubber cork into the beaker full of water.

Answer the following questions:

1. Name the type of force acting on each object as contact and non contact force.

2. Name the agent applying the force.

3. Name the effect produced by the force in each case.

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Activity Sheet 2.

Understanding of Balanced and Unbalanced Force – Application to real life situations

Examine the following examples carefully and answer the questions following them.

1. A boy standing with a box held in his hand.

2. A man jumping down with the help of a parachute.

3. A car moving in a uniform motion.

4. A rolling football stopping due to friction.

5. A weight lifter lifting weights.

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Name all the forces acting on the given objects. Also show the direction of forces with arrow

heads. Greater force will be shown with a longer arrow.

1. Book ……………………………………………………………………..

2. Parachute

3. Car ………………………………………………………………………..

4. Ball ……………………………………………………………………….

5. Weights ………………………

…………………………………………………………………..

Teacher Student Support Material cum Activity Sheet

Concept Development – Balanced and Unbalanced Force

Force A Vector Quantity

A force is a vector quantity. A vector quantity is a quantity which has both magnitude and

direction. To fully describe the force acting upon an object, you must describe both the

magnitude (size or numerical value) and the direction. Thus, 10 newtons is not a full

description of the force acting upon an object. In contrast, 10 newtons, downwards is a

complete description of the force acting upon an object; both the magnitude (10 newtons) and

the direction (downwards) are given.

Because a force is a vector which has a direction, it is

common to represent forces using diagrams in which a

force is represented by an arrow. The size of the arrow is

reflective of the magnitude of the force and the direction of

the arrow reveals the direction which the force is

acting.Such diagrams are known as free-body diagrams.

Furthermore, because forces are vectors, the affect of an

individual force upon an object is often canceled by the

affect of another force. For example, the affect of a 20-

Newton upward force acting upon a book is canceled by the affect of a 20-Newton downward

force acting upon the book. In such instances, it is said that the two individual forces balance

each other; there would be no unbalanced force acting upon the book.

Other situations could be imagined in which two of the individual vector forces cancel each

other ("balance"), yet a third individual force exists that is not balanced by another force. For

Activity Sheet 3

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example, imagine a book sliding across the rough surface of a table from left to right. The

downward force of gravity and the upward force of the table supporting the book act in

opposite directions and thus balance each other. However, the force of friction acts leftwards,

and there is no rightward force to balance it. In this case, an unbalanced force acts upon the

book to change its state of motion

An object at rest tends to stay at rest and an object in motion tends to stay in motion with the

same speed and in the same direction unless acted upon by an unbalanced force.

The unbalanced force refers to that force which does not become completely balanced (or

canceled) by the other individual forces. If either all the vertical forces (up and down) do not

cancel each other and/or all horizontal forces do not cancel each other, then an unbalanced

force exists. The existence of an unbalanced force for a given situation can be quickly realized

by looking at the free-body diagram for that situation.

Free-body diagrams for three situations are shown below. Note that the actual magnitude of

the individual forces are indicated on the diagram.

In each of the above situations, there is an unbalanced force. In each situation there is a net

force acting upon the object. The net force is the vector sum of all the forces which act upon an

object. That is to say, the net force is the sum of all the forces, taking into account the fact that a

force is a vector and two forces of equal magnitude and opposite direction will cancel each

other out. At this point, the rules for summing vectors (such as force vectors) will be kept

relatively simple. Observe the following examples of summing two forces:

1. Determining the Net Force

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Observe in the diagram above that a downward vector will provide a partial or full

cancellation of an upward vector. And a leftward vector will provide a partial or full

cancellation of a rightward vector. The addition of force vectors can be done in the same

manner in order to determine the net force (i.e., the vector sum of all the individual forces).

Consider the following example. Three situations are given below in which the net force is

determined by summing the individual force vectors which are acting upon the objects.

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TESTING TIME

Formative Assessment

Q1. Free-body diagrams for four situations are shown below. For each situation,

determine the net force acting upon the object.

ANS Situation A ………… Situation C ……………

Situation B………….. Situation D………………

2. Free-body diagrams for four situations are shown below. The net force is known for each

situation. However, the magnitudes of a few of the individual forces are not known. Analyze

each situation individually and determine the magnitude of the unknown forces.

ANS ……………………… ………………………….. ……………………………

……………………………

17SCIENCE UNIT - 2

2. The Effect Of Unbalanced Force

Activity Sheet 4

The effect of a net force (i.e., an unbalanced force) is non uniform of accelerated motion. In a

previous unit, several means of representing accelerated motion (position-time and velocity-

time graphs, ticker tape diagrams, velocity-time data, etc.) were discussed. Combine your

understanding of acceleration and the newly acquired knowledge that a net force causes an

acceleration to determine whether or not a net force exists in the following situations.

Vector Addition – Developing Scientific Skills

Two vectors can be added together to determine the result (or resultant). This process of

adding two or more vectors has already been discussed in the previous activity sheet.

Description of Motion Net Force: Yes or No? Give Reason.

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In this unit, the task of summing vectors will be extended to more complicated cases in which

the vectors are directed in directions other than purely vertical and horizontal directions. For

example, a vector directed up and to the right will be added to a vector directed up and to the

left. The vector sum will be determined for the more complicated cases shown in the diagrams

below.

There are a variety of methods for determining the magnitude and direction of the result of

adding two or more vectors. The two methods which will be discussed in this lesson and used

throughout the entire unit are:

• the Pythagorean theorem and trigonometric methods

The Pythagorean Theorem

The Pythagorean theorem is a useful method for determining the result of adding two (and

only two) vectors which make a right angle to each other. The method is not applicable for

adding more than two vectors or for adding vectors which are not at 90-degrees to each other.

The Pythagorean theorem is a mathematical equation which relates the length of the sides of a

right triangle to the length of the hypotenuse of a right triangle.

Activity Sheet 5 – Extended Learning

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To see how the method works, consider the following problem:

Shyla travels 11 km, north and then travels 11 km east from her home. Determine her resulting

displacement.

This problem asks to determine the result of adding two displacement vectors which are at

right angles to each other. The result (or resultant) of walking 11 km north and 11 km east is a

vector directed northeast as shown in the diagram to the right. Since the northward

displacement and the eastward displacement are at right angles to each other, the

Pythagorean theorem can be used to determine the resultant (i.e., the hypotenuse of the right

triangle).

The result of adding 11 km, north plus 11 km, east is a vector with a magnitude of 15.6 km.

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Let's test your understanding with the following two practice problems. In each case, use the

Pythagorean theorem to determine the magnitude of the vector sum.

Ans …………………………………….. Ans ……………………………………..

Formative Assessment

Force and Motion - What Do You Believe?

The following statements pertain in one way or another to common notions regarding force

and motion.

Identify each statement as being either true (T) or false (F). If false correct the statement.

1. A force is required to keep an object moving in a given direction.

……………………………………………………………………………

2. An upward moving object must be experiencing (or at least usually does experience)

an upward force.

……………………………………………………………………………

3. A rightward moving object must be experiencing (or at least usually does experience)

a rightward force.

………………………………………………………………………………

Activity Sheet 6

21SCIENCE UNIT - 2

4. A ball is thrown into the air and is moving upwards and rightwards towards its peak.

The ball experiences a force which is directed upwards and rightwards.

………………………………………………………………………………

5. If a person throws a ball with his hand, then the force of the hand upon the ball isexperienced

by the ball for at least a little while after the ball leaves the hand.

………………………………………………………………………………

6. A cannonball is shot from a cannon at a very high speed. The force of the explosionwill be

experienced by the cannonball for several seconds (or a least a little while).

……………………………………………………………………………..

7. If an object is at rest, then there are no forces acting upon the object.

……………………………………………………………………

Formative assessment - Revision On Force and Motion

Multiple Choice Questions

Question 1 : Inertia is ________

1. a property of matter

2. a type of force

3. the speed of an object

4. none of the above

Answer: ………

Question2 : A and B are two objects with masses 100 kg and 75 kg respectively, then ________

.

1. both will have the same inertia

2. B will have more inertia

3. A will have more inertia

4. both will have less inertia

Answer: ……….

Activity Sheet 7

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Question3 : The resultant of balanced forces is ________

1. non zero

2. equal to zero

3. not equal to zero

4. equal to the acceleration produced in the body

Answer: ……….

Question4 : The physical quantity, which is the measure of inertia, is ________

1. density

2. weight

3. force

4. mass

Answer: ……….

Question 5 : The sparks produced during sharpening of a knife against a grinding wheel

leaves the rim of the wheel tangentially. This is due to ________

1. inertia of rest

2. inertia of motion

3. inertia of direction

4. force applied

Answer: ……….

Question 6 : The law that gives a qualitative definition of force is ________

1. Newton's second law of motion

2. Law of inertia

3. Newton's third law of motion

4. Law of gravitation

Answer: ………

23SCIENCE UNIT - 2

Question 7 : Name the property of matter due to which a body continues in its state of rest or

uniform motion unless an external force acts on it.

1. Inertia

2. Elasticity

3. Viscosity

4. Density

Answer: ………

Question 8 : The S.I. unit of force is

1. Erg

2. Joule

3. Newton

4. Dyne

Answer: ……

Question 9: When a force of 1N acts on a mass of 1kg that is free to move, the object moves

with

1. a speed of 1 m/s

2. a speed of 1 km/s

3. an acceleration 10 m/s2

4. an acceleration of 1 m/s2

Answer: ……..

Question 10: The acceleration in a body is due to

1. balanced force

2. unbalanced force

3. Mass

4. electrostatic force

Answer: …….

24 SCIENCE UNIT - 2

Question 11: When an object undergoes acceleration

1. its speed always increases

2. its velocity always increases

3. it always falls towards the Earth

4. a force always acts on it

Answer: …….

Question 12: A force of 10 N is acting on an object of mass 10 kg. What is the acceleration

produced in it?

1.

2.

3. 100 m/s2

4. 100 m/s

Answer: …….

Question 13: What is the force acting on an object of mass 10 kg moving with a uniform

velocity of 10 m/s ?

1. 100 N

2. 10 N

3. 0

4. 1 N

Answer: …….

Question 14: An athlete can take a longer jump if he comes running from a distance as

compared to that when he jumps suddenly. Identify the type of inertia.

1. Inertia of rest

2. Inertia of motion

3. Inertia of direction

4. Inertia of position

Answer: ………

1 m/s2

1 m/s

25SCIENCE UNIT - 2

Question 15: 1 newton = ________

1.

2.

3.

4.

Answer: ……..

Question 16: The physical quantity, which is equal to change in momentum, is

1. force

2. impulse

3. acceleration

4. velocity

Answer: ……..

Question 17: The physical quantity, which is equal to rate of change of momentum, is

1. displacement

2. acceleration

3. force

4. impulse

Answer: ……..

Question 18: 1kg m/s = _________.

1. 1 N s

2. 1 N

3. 1 N m

4. 10 N s

Answer: ……..

26 SCIENCE UNIT - 2

Question 19: An example for a vector quantity is __________

1. speed

2. momentum

3. distance

4. length

Answer: …….

Question 20: The momentum of a toy bus of 0.01 kg moving with a velocity of 5 m/s is

1. 0.005 kg m/s

2. 0.05 kg m/s

3. 0.005 N s

4. 0.5 kg m/s

Answer: ....................

Question 21: The product of mass and velocity is known as ____________ .

1. acceleration

2. force

3. momentum

4. velocity

Answer: ……..

Question 22: What is the momentum of a man of mass 100 kg when he walks with a uniform

velocity of 2 m/s?

1.

2. 200 N

3.

4.

Answer: ………

27SCIENCE UNIT - 2

Question 23: The two factors on which the momentum of a body depends are ______ and

_________ .

1. velocity, time

2. mass, weight

3. mass, distance

4. mass,velocity

Answer: ……..

Question 24: Momentum of a massive object at rest is _______.

1. very large

2. very small

3. zero

4. none of the above

Answer: ……..

Question 25: The resultant of action and reaction forces is _______.

1. greater than zero

2. less than zero

3. zero

4. none of the above

Answer: ……….

28 SCIENCE UNIT - 2

Unit - Force and Motion ; Topic – Newton’s First Law

Activity 1

Activity 2

Warming Up

Teachers should talk about daily life situations sitting in a vehicle when the brakes have

suddenly been applied, trying to push a heavy shopping cart, or observing a fish swimming in

water, and hence witnessing Sir Isaac Newton’s Laws of Motion. Newton’s three laws of

motion govern 99 percent or more of our everyday experiences—from how the planets orbit

the Sun to how a person rides a bicycle. This lesson is designed to help students understand

the relationship between force and motion. Students will observe objects in motion and

speculate why they move the way they do. They will then discuss the meaning of Newton’s

three laws of motion and apply these laws to everyday situations

You can do a simple inertia experiment to demonstrate this. You'll need a hard-boiled egg and

a raw egg for this activity. First, spin the hard-boiled egg on its side. When it's going fast,

gently put your fingers down on it to stop it and then move your hand off immediately when it

stops. Next, spin the raw egg. Stop it in the same way you did with the hard-boiled egg. After

you let go, what happens? The egg should start to turn again. This is because the motion of the

liquid within the egg is still going; the force you exerted was not enough to stop both the

inertia of the shell and the inertia of the liquid inside of it. If you held the egg longer, enough

force would have been exerted to stop the egg completely.The results of the experiment fit in

with the Law of Inertia: an object will continue to remain in one state until sufficient outside

force acts upon it, either to put it in motion or to bring it to rest.

The greater mass or velocity an object has, the greater its inertia. You can test this the next time

you're at the grocery store. It takes a strong push to get a loaded shopping cart moving, but

once it gathers speed it keeps going even if you let go of the handle. When you stop a moving

cart full of groceries, it takes much more force to stop it than an empty cart (one with less mass).

Likewise, it takes more force to brake a fast-moving bike than a slow one (one with less

velocity), even though the mass of each is equal.

8 Student and Teacher Support Materials

29SCIENCE UNIT - 2

PRE-LESSON ACTIVITIES TO BUILD BACKGROUND KNOWLEDGE

LESSON DEVELOPMENT

Activity 4 ;.Soda Pull

Activity 3

Ask students if they have ever seen a magician pull a tablecloth out from underneath a place

setting without breaking the dishes. Demonstrate this trick by quickly pulling the table cloth

down and away from your table.(Note: The key to performing this trick successfully is using a

quick, downward motion.) Ask students to explain why they think the objects on the table did

not fall off the table and break. Explain to students that this magic trick is best explained with

Sir Isaac Newton’s Laws of Motion. Quickly assess students’ knowledge of Newton. Have

students explain who he was and describe some of his major accomplishments.

Discuss the experiment with students. And find the answers to following questions

• Does the mass (weight) have any effect? Why?

• Does the type of object – rough or glossy, you added to the

cloth have an effect? In what way? Why?

• How does this experiment relate to Newton’s

first law of motion?

Hands on Lab / classroom activities for students

The purpose of this session is to demonstrate a variety of strategies that help children learn

observation techniques, organize data collection and develop meaningful relationships

between the activity and a child-generated concision. These will include questioning

techniques (oral and written), group and class charts, framing, student constructed data

charts, constructing inferences from observations, identifying variables, making dependable

predictions, finding evidence to prove your theory and writing activity-appropriate

conclusions.

Workshop Focus: Identifying and Graphing Variables

Purpose: To demonstrate the effect of weight on inertia

Materials: 2 liter soda bottle, rubber band, 30 cm of string, scissors, ruler

30 SCIENCE UNIT - 2

Procedure:

Data Table:

Questions:

Activity 5 ; Friction

Procedure:

Tie the string to the rubber band and put the rubber band around the bottom of the bottle. Pull

on the string until the bottle starts to move. Measure the amount that the rubber band

stretches. Repeat with different amounts of water in the bottle.

Amount of water used (in milliliters) ,Distance rubber band stretched (in cm)

Using the data, make a graph.

1. What is your independent variable? dependent variable?

2. Which data should be graphed on the horizontal axis of your graph?

3. What happened when you added more water to the bottle?

4. Does the stretch of the rubber band depend on how hard you pull or on how much

water is in the bottle?

5. Did all students pull the rubber band the same way? What could cause an error in

your conclusion?

6. Write a good definition for Inertia.

Workshop Focus: Writing a Summary

Purpose: To compare different surface, testing how much force is required to move an object

over each surface

Materials: empty 1 gal milk bottle, Newton (spring) scale, rubber band, sandpaper strip, wax

paper, Pam, strip of poster board, playing cards, wheeled carrier large enough to

hold the milk bottle, masking tape

Pour 1,000 ml of water into the milk bottle; place the rubber band around the bottle, even with

the water level. Attach a Newton scale to the rubber band. Tape the other materials down on

your work surface. Pull the bottle along the desk, or floor, and measure how many Newton’s

are required to keep it moving. Record this information. Repeat these steps for each of the

different surfaces.

31SCIENCE UNIT - 2

Data Table:

Type of surface

Newton’s table, sandpaper, wax paper, Pam sprayed surface, poster board, carpet, wheels

Make a bar graph using the data from your table.

Questions:

1. What parts of your experiment stayed the same?

2. Why did you use different surfaces?

3. What caused the measurements to be different?

4. What was your control in this experiment?

Conclusion:

Summarize this experiment in paragraph form.- purpose of the experiment, summary of the

procedure, summary of your results, explanation of results, the rule for this experiment

PRE-LESSON ACTIVITIES TO BUILD BACKGROUND KNOWLEDGE

Everyone unconsiously knows the Second Law. Everyone knows that heavier objects

require more force to move the same distance as lighter objects.

Demonstrate this principle by dropping a rock or marble and a wadded-up piece of paper at

the same time. They fall at an equal rate €”their acceleration is constant due to the force of

gravity acting on them. However, the rock has a much greater force of impact when it hits the

Unit - Force and Motion ; Topic – Newton’s Second Law

ACTIVITY 1

32 SCIENCE UNIT - 2

ground, because of its greater mass. If you drop the two objects into a dish of sand or flour, you

can see how different the force of impact for each object was, based on the crater made in the

sand by each one.

Another way to show this is two push off two toy cars or roller skates of equal mass at the same

time, giving one of them a harder push than the other. The mass is equal in both, but the

acceleration is greater in the one that you exerted greater force on.

Activity 2

Take the class outside. Select four student volunteers. Have each of them hit a tennis ball with a

racket and ask the rest of the class to observe what happens.

Ask the class what would happen if the students tried to hit a basketball with the racket. Then

have each of the four volunteers try to hit a basketball with the racket. Ask the volunteers to

describe what happened. and answer the following questions

What is Newton’s second law of motion?

How does pushing a shopping cart exemplify

Newton’s second law?

How does Newton’s second law apply to hitting

a tennis ball and basketball?

Hands on Lab / classroom activities for students

Activity 3;. Brick Pull

Workshop Focus: Inferencing and Predicting

Purpose: To show the relationship between mass and acceleration (the amount of Newton’s

required to move an object is dependent on the mass of the object)

Materials: 3 bricks or large books, string, Newton scale

Procedure: Tie the string around the long sides of the brick. Attach a Newton scale to the

string. Pull and record the number of Newton’s required just to start the brick moving. Repeat

for 2 and 3 bricks.

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LESSON DEVELOPMENT

33SCIENCE UNIT - 2

Make a Data Table:

Find Average N for 1 brick, 2 bricks, 3 bricks

Make a line graph for the average number of newtons per brick.

Questions:

1. What do you predict will be the number of newtons required for moving 4 bricks? For

6 bricks? 10 bricks?

2. Using a different colored pencil, show your prediction on the graph.

3. Test your prediction.

4. What would happen if you used four bricks and pushed with 2 newtons and at the

same time pulled with 2 newtons?

5. Would you need the same number of newtons to push the bricks instead of pulling

them? Explain your answer.

6. Test your predictions.

7. Do you need the same number of newtons to lift up the bricks? Explain your answer.

8. Test your prediction.

Conclusion:

What is the rule for this experiment?

Pre-lesson Activities To Build Background Knowledge

Activity 1

Newton's Third Law of Motion says that "for every action, there is an equal and opposite

reaction." Use a pair of roller skates and a ball to show how this works. What happens when

you're standing still in skates and then throw a ball hard? The force of throwing the ball pushes

your skates (and you) in the other direction.

Activity 2

You can also demonstrate this using Newton's Swing. This apparatus consists of steel balls

suspended on a frame. When the ball on one end is pulled back and then let go, it swings into

the other balls. The ball on the opposite end then swings up with an equal force to the first ball,

Unit - Force and Motion ; Topic – Newton’s Third Law

34 SCIENCE UNIT - 2

as shown in the illustration on the right. The force of the first ball causes and equal and

opposite reaction in the ball at the other end.

Activities Catering To Multiple Intelligence Skills

Hands on Lab / classroom activities for students

Let's study how a rocket works to understand

Newton's Third Law.

The rocket's action is to push down on the ground with the force of its powerful engines, and

the reaction is that the ground pushes the rocket upwards with an equal force.

Balloon racers rely on Newton's Third Law of Motion. As the air rushes backward out of the

balloon it pushes the car forward in the opposite direction with an equal force. Your job is to

make the most of this force!

Unit - Force and Motion ; Topic – Newton’s Third Law

Activity – 3

Activity 4 – Balloon Racers

35SCIENCE UNIT - 2

The rules to this activity are simple:

The car must be powered by balloons.

You can build the car out of anything.

It must have at least three wheels. Wheels are defined as anything that is round and

goes around.

The wheels cannot be wheels from a toy car. They must be made out of something

that was not originally meant to be used as wheels.

The car may not leave the ground.

The car must be capable of traveling at least 5 meters. There are several important things to

keep in mind when designing and building your balloon racer. The first thing to do is choose

the material to build the chassis or body of the car. The chassis should be both light and sturdy,

for this reason Styrofoam makes a very good chassis. It is also important to design a chassis

that is long enough. Short cars tend to spin out

The second thing to do is build and mount the wheels. Wheels can be made out of about

anything that is round, such as CDs caps and lids. The hard part, however, is getting them

mounted straight with little friction. If the wheels are not mounted straight or are not free to

spin smoothly, the car will not perform well.

Once the wheels are mounted on the chassis it is time to put a balloon onto the car. Having the

balloon attached to a pen barrel so that the air comes out in a smooth manner helps. Another

helpful approach is to double up a balloon so that it is twice as thick.

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Teacher and Student Support Material

36 SCIENCE UNIT - 2

Unit - Force and Motion ; Topic – Newton’s Laws of motion

Worksheet 1 – Application to real life situations

Name the Newton’s law to match its application

1. A magician pulls a tablecloth out from under dishes and glasses on a table without

disturbing them.

Answer

2. A person’s body is thrown outward as a car rounds a curve on a highway.

Answer

3. Rockets are launched into space using jet propulsion where exhaust accelerates out from

the rocket and the rocket accelerates in an opposite direction.

Answer

4. A picture is hanging on a wall and does not move.

Answer

5. A person not wearing a seatbelt flies through a car window when someone slams on the

breaks because the person’s body wants to remain in continuous motion even when the

car stops.

Answer

6. Pushing a child on a swing is easier than pushing an adult on the same swing, because the

adult has more inertia.

Answer

7. A soccer ball accelerates more than a bowling ball when thrown with the same force.

Answer

8. A soccer player kicks a ball with their foot and their toes are left stinging.

Answer

9. A student leaves a pencil on a desk and the pencil stays in the same spot until another

student picks it up.

Answer

10. Two students are in a baseball game. The first student hits a ball very hard and it has a

greater acceleration than the second student who bunts the ball lightly.

Answer

9 Annexures

37SCIENCE UNIT - 2

Unit - Force and Motion ; Topic – Newton’s Laws of motion

Worksheet 2 – Evaluation

What is inertia?

What is Newton’s first law of motion?

What is Newton’s second law of motion? What

is the formula that expresses this law?

What does Newton’s third law of motion state

about action-reaction forces?

Would you be surprised if a ball flew up into

the air by itself? Why? According to Newton’s

first law, what is needed to make the ball move?

If a given force is applied to two objects of different

mass, which object will accelerate more?

How do rockets exemplify Newton’s third law of motion?

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38 SCIENCE UNIT - 2

Unit - Force and Motion ; Topic – Newton’s Laws of motion

Worksheet 3 – Developing Scientific Skills

1 A 4kg object is moving across a frictionless surface with a constant velocity of 2 m/s.

Determine the force necessary to maintain this state of motion

2 An object sits on a frictionless surface. There is a 16 N force being applied to an object and

its acceleration is at 2 m/s/s. What is its mass?

3 Two forces act on a body of mass of 2 kg. One is 10N North and the other 4N South. Find

resultant acceleration.

4 A mass of 5 kg has a weight of

5 The same horizontal force is applied to objects of different mass. Which of the following

graphs illustrates the experimental results? ]

5 N.

9.8 N.

49 N.

98 N.

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39SCIENCE UNIT - 2

6 Four students perform an experiment by pulling an object horizontally across a

frictionless table. They repeat the experiment on several other objects of different masses,

always applying just enough force to produce the same acceleration. They each graph the

results, individually. Which student's graph is correct?

7 A 2000-kg car travelling at 30 m/s comes to rest in 60 m. What constant force brought it to a

stop?

1000 N

1500 N

10000 N

15000 N

A body with a mass of 1.0 kg is accelerated by a force F = 2.0 N. What is velocity of this body

after 5.0 s of motion?

A car of mass m=1200 kg is traveling at a speed of 50km/h. Suddenly the brakes are applied

and the car is brought to a stop over a distance of 20m. Assuming constant breaking force find:

(1) the magnitude of the breaking force,

(2) the time required to stop.

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40 SCIENCE UNIT - 2

Unit - Force and Motion ;Topic – Conservation of momentum

Building Background Knowledge

Consider an example-when there happens a collision between moving train & bus , then

nothing happens to train and bus gets totally crushed , why?

Also, when train halts at the station, then it takes some time to do that.

But it is not true for bus . Why? Because of high mass of train.

Thus, by seeing above examples we can say that heavier bodies (like train) takes some time to

bring it's velocity to zero when brakes are applied though train and bus are moving with the

same velocity. Therefore,to describe the motion of body , not only velocity is considered but

mass is also taken into account. The total quantity of motion possessed by a moving body is

known as the momentum of the body

41SCIENCE UNIT - 2

Unit - Force and Motion ;Topic – Conservation of momentum

Lesson Development

In the absence of external forces , the total momentum of the body is conserved.

Example-when the bullet is fired , it moves in the forward direction and the gun kicks

backward. It is because before firing total momentum of system constituted of barrel and gun

is zero. When bullet is fired it gains some momentum(due to velocity acquired by it) but to

nullify this momentum gain, gun moves in backward direction such that it has momentum

equal in magnitude to momentum of bullet with opposite direction.

Although velocity has been referred to, it is not the total velocity of a closed system that

remains constant. If it was, then firing a gun would cause the gun to recoil at the same velocity

as the bullet! The gun does recoil, but at a much lower velocity than the bullet. Newton's third

law tells us

Fgun on bullet = - Fbullet on gun ,

and assuming a constant force for simplicity, Newton's second law allows us to change this to

42 SCIENCE UNIT - 2

Unit ; Force and Motion Topic ; Conservation of momentum

Worksheet 4 – Application to real life situations

1. When fighting fires, a firefighter must use great caution to hold a hose which emits large

amounts of water at high speeds. Why would such a task be difficult?

2 A large truck and a Volkswagen have a head-on collision.

a. Which vehicle experiences the greatest force of impact?

b. Which vehicle experiences the greatest impulse?

c. Which vehicle experiences the greatest momentum change?

d. Which vehicle experiences the greatest acceleration?

3 If a ball is projected upward from the ground with ten units of momentum, what is the

momentum of recoil of the Earth? Do we feel this? Explain

4 If a 5-kg bowling ball is projected upward with a velocity of 2.0 m/s, then what is the

recoil velocity of the Earth (mass = 6.0 x 1024 kg).

5 A baseball player holds a bat loosely and bunts a ball. Express your understanding of

momentum conservation by filling in the tables below.

43SCIENCE UNIT - 2

Worksheet 5

Numerical Skills

Conservation of Momentum ; Unit - Force

1. In a physics lab, 0.500-kg cart (Cart A) moving rightward with a speed of 92.8 cm/s

collides with a 1.50-kg cart (Cart B) moving leftward with a speed of 21.6 cm/s. The

two carts stick together and move as a single object after the collision. Determine the

post-collision speed of the two carts.

2. A 25.0-gram bullet enters a 2.35-kg watermelon and embeds itself in the melon. The

melon is immediately set into motion with a speed of 3.82 m/s. The bullet remains

lodged inside the melon. What was the entry speed of the bullet? (CAUTION: Be

careful of the units on mass.)

3. A 25.0-gram bullet enters a 2.35-kg watermelon with a speed of 217 m/s and exits the

opposite side with a speed of 109 m/s. If the melon was originally at rest, then what

speed will it have as the bullet leaves its opposite side? (CAUTION: Be careful of the

units on mass.)

4. In a physics lab, a 0.500-kg cart (Cart A) moving with a speed of 129 cm/s encounters

a magnetic collision with a 1.50-kg cart (Cart B) which is initially at rest. The 0.500-kg

cart rebounds with a speed of 45 cm/s in the opposite direction. Determine the post-

collision speed of the 1.50-kg cart.

5. A 3000-kg truck moving rightward with a speed of 5 km/hr collides head-on with a

1000-kg car moving leftward with a speed of 10 km/hr. The two vehicles stick

together and move with the same velocity after the collision. Determine the post-

collision velocity of the car and truck. (CAREFUL: Be cautious of the +/- sign on the

velocity of the two vehicles.)

6. During a goal-line stand, a 75-kg fullback moving eastward with a speed of 8 m/s

collides head-on with a 100-kg lineman moving westward with a speed of 4 m/s. The

two players collide and stick together, moving at the same velocity after the collision.

Determine the the post-collision velocity of the two players. (CAREFUL: Be cautious

of the +/- sign on the velocity of the two players.)

(Courtesy www.physicsclassroom.com)

44 SCIENCE UNIT - 2

Work Sheet 6 – Developing Problem Solving Skill

Momentum and Collisions ; Unit - Force

1. Determine the post-collision velocities of the following objects or combination of

objects.

a. b.

c. d.

e. f.

45SCIENCE UNIT - 2

Work Sheet 7 - Developing Numerical Solving Skills

Momentum and Collisions ; Unit – Force

1. A 2.1-kg brick is placed gently upon a 2.9-kg cart originally moving with a speed of

26 cm/s.

Determine the post-collision speed of the combination of brick and cart.

2. A 98-kg fullback is running along at 8.6 m/s when a 76-kg defensive back running

in the same direction at 9.8 m/s jumps on his back. What is the post-collision speed

of the two players immediately after the tackle?

3. A 0.112-kg billiard ball moving at 154 cm/s strikes a second billiard ball of the same

mass moving in the opposite direction at 46 cm/s. The second billiard ball rebounds

and travels at 72 cm/s after the head-on collision. Determine the post-collision

velocity of the first billiard ball.

4. A 225-kg bumper car (and its occupant) is moving north at 98 cm/s when it hits a

198-kg car(occupant mass included) moving north at 28 cm/s. The 198-kg car is

moving north at 71 cm/s after the head-on collision. Determine the post-collision

velocity of the 225-kg car.

5. A 4.88-kg bowling ball moving east at 2.41 m/s strikes a stationary 0.95-kg bowling

pin.

Immediately after the head-on collision, the pin is moving east at 5.19 m/s. Determine the

post collision velocity of the bowling ball.

46 SCIENCE UNIT - 2

1. SyllabusUNIT II Materials (Foundation and Extension)

1. Materials around us

• Kinds of materials( on basis of shape, size, texture, state)• Materials that are good conductors of heat• Materials that are poor conductors of heat• Specific heat capacity

2. Materials in our clothing

• Clothes that are good insulators• Clothes that keep us cool ( white Vs Black clothes)• Cotton Vs synthetic fabrics

10 Syllabus Coverage (Chemistry)

47SCIENCE UNIT - 2

At the end of this unit students should be able to-

Section 2

Section 1

• Identify types of materials around them – wood, rocks, bricks, cotton wool, water,

oil, gases, soot etc

• Observe that solids differ from each other in shape (crystalline, amorphous),

texture (smooth, rough, slippery, sharp), lustre, sonority, colour

• Observe and understand that liquids differ in colour, smell, density, miscibility

with water and with other liquids, viscosity and volatility.

• Observe and understand that gases differ in colour, smell, solubility in water, rate

of diffusion.

• Understand that 2 substances may be in the same state but different phases – oil

and water.

• Recall that metals are good conductors of heat and substances like wood and

plastics are poor conductors of heat.

• Recall mode of transfer of heat in solids, liquids and gases.

• Define heat capacity and specific heat capacity of a substance.

• Apply the concept of heat capacity in problem solving.

• Explain that clothes have air holes that trap air to trap body heat

• Explain why it is better to wear 2 thin sweaters in winters than 1 sweater of the

combined thickness.

• Apply knowledge of insulating to other materials used for clothing

11 Scope Document

48 SCIENCE UNIT - 2

• State and explain why we wear white / pale colours in summers and black/ dark

colours in winters.

• State and explain why we wear cotton fabrics and should not wear synthetic

fabrics in summers.

Section 1

1. Expose students to different kinds of solids, liquids and gases and ask them to

observe and describe each material. This could be done in the laboratory /

classroom or by taking the students outdoors.

2. Activities involving mixing miscible liquids like water and alcohol. ( some

coloured ink may be added) and immiscible liquids like oil and water. Use this to

explain the concept of phases.

3. Perform simple experiments to show that metals are good conductors of heat and

non metallic materials like wood and plastics are poor conductors.- simple

experiments showing that while cooking a metallic spoon soon gets very hot and

cannot be held while a spoon with a wooden handle can easily be hand held. A very

interesting experiment in the first web link below. You may modify it as desired.

4. Simulations to show heat conduction in solids. Convection currents can be shown

with the help of an experiment in class.

5. Simple experiments to show that heat capacities and specific heat capacities of

different solids and liquids are different.

Section 2

1. An experiment where students take many coke cans and put hot water in each( same

temperature). Wrap one in cotton wool, another in jute , 3rd in cotton fabric, 4th in a

piece of some woollen fabric etc… but leave one without any cover. Note the

temperature of each after regular time intervals / 20 minutes.

2. Similar experiments can be performed by taking 2 bottles with water. Note the

temperature. Wrap one in white paper and one in black paper. Put both in the sun.

Record the final temperature in both bottles after some time.

Suggested Activities

49SCIENCE UNIT - 2

In these experiments, bring out the concept of a fair test, control experiment. Get higher

ability students to design such experiments. Get students to identify dependent, independent and control variables.Modify activities based on ability of the students and class dynamics.

At the end of the unit there must be some questions to assess the student’s understanding

of the topic and ability to apply knowledge.

• Assignment questions based on conduction of heat by solids.

• Questions based on transfer of heat by conduction, convection and radiation.

• Questions on specific heat capacity

• Numericals on specific heat capacity.

• Reasoning and questions based on explanations for clothes that are good

insulators, absorb heat, reflect heat etc.

• There should be at least one design experiment task for this topic.

Links very well with physics – topic of heat.

WEB LINKS

http://www.wired.com/geekdad/2007/04/experiment_whic/

http://www.engineeringtoolbox.com/specific-heat-solids-d_154.html

http://ezinearticles.com/?Materials-Which-Absorb-Solar-Energy&id=1733991

http://www.bukisa.com/articles/64635_color-and-heat-absorption

http://www.colormatters.com/colorheat.html

http://chestofbooks.com/crafts/needlework/Home-Economics/How-Our-

Clothing-Keeps-Us-Healthy-Part-3.html

END OF UNIT QUESTIONS

CROSS CURRICULAR LINKS

50 SCIENCE UNIT - 2

12 Rubrics Of Assessment For Learning

Unit II, Materials- SECTION -I

Parameter Beginning

(0)

Approaching

(1)

Meeting

(2)

Exceeding

(3)

Is able to identify types of materials around in nature.

Understands that liquids differ in colour, smell, density, miscibility with water and with other liquids, viscosity and volatility.

Understands that gases

differ in colour, smell,

solubility in water, rate of

diffusion.

Understands that two

substances may be in the

same state but different

phases – oil and water.

Is able to apply the

concept, that metals are

good conductors of heat

and substances like wood

and plastics are poor

conductors of heat.

Is able to recall mode of transfer of heat in solids, liquids and gases

51SCIENCE UNIT - 2

Is able to apply knowledge about heat capacity and specific heat capacity of a substance.

Apply the concept of heat capacity in problem solving

Is able to solve numerical on concept of heat capacity.

Unit II, Materials SECTION -II

Parameter Beginning

(0)

Approaching

(1)

Meeting

(2)

Exceeding

(3)

Is able to explain that clothes have air holes that trap air to trap body heat

Is able to explain why it is better to wear 2 thin sweaters in winters than 1 sweater of the combined thickness.

Is able to apply knowledge of insulating to other materials used for clothing

Is able to state and explain

why we wear white / pale

colours in summers and

black/ dark colours in

winters.

Is able to state and explain why we wear cotton fabrics and should not wear synthetic fabrics in summers.

52 SCIENCE UNIT - 2

Students will be able to:Recall that metals are good conductors of heat Recall mode of transfer of heat in solids. Understand that different metals have different rates of heat transfer. Students study conduction of heat through solids The students are asked to make hypothesis on how and at what intervals pins will fall if material of the rod was different.

Steps to be followed

Tools/ Activity used Description

Warm up A knowledge - annexure1Teacher support-annexure 2

start up worksheet to check background

This sheet can be used as a starter to the unit. The aim of this exercise is to allow students to recall their experiences and appreciate the large variety of material present around us with varied physical properties pertaining to their texture, shape, size, colour, floatation, transparency, conduction, etc.

Pre content

Pre Content,

Activity- worksheet-2- annexure 3

Teacher support –annexure4

Questionnaire- annexure5

This activity should make the

student able to identify types of materials around them based on their characteristics.

Content

Activity-Worksheet-3, annexure6

Teacher support-annexure7

Questions- annexure 8

Students should be able to understand that two substances may be in the same state but different phases. Activity: To identify the solution of two liquids as miscible, immiscible and predict their phases.

Activity-Worksheet-4, annexure9Teacher support-annexure10Questions- annexure 11Web Links:http://www.wired.com/geekdad/2007/04/experiment_whichttp://www.scribddownload.com

Activity: To show that metals are good conductors of heat and non metallic materials like wood and plastics are poor conductors of heat.

Activity-Worksheet-5, annexure12-Conduction in solidsTeacher support- Annexure13Power point presentationAnimation showing conduction through solidsVideos download in annexure-http://www.youtube.com/watch?v=fhgvftgqArQ&feature=relatedhttp://www.youtube.com/watch?v=oWjDnNr5T6A&feature=related

Extension and designing an activity

13 Lesson Template for UNIT 2:Materials: Section 1

53SCIENCE UNIT - 2

Steps to be followed

Tools/ Activity used Description

Activity-Worksheet-6, annexure 14Teacher support-annexure15Convection in Liquids

Students-Recall that rate of diffusion increases with temperature.-Relate diffusion of colour in water to the mode of transfer of heat in liquids.-Students study convection of heat through liquids and its dependence on temperature.

Activity- Worksheet-7 annexure 16Teacher support –annexure 17Convection in gasesVideoshttp://www.youtube.com/watch?v=VzE_IPedujc&feature=related

Students - Recall the mode of transfer of heat in gases. -Relate that hot air is lighter than cold air and moves up. -Students study convection of heat through gases

Research and Exploration

Activity worksheet -8- Annexure 18Questions worksheet-Annexure 19Teacher support-Annexure 20Suggested activitiesWeb Site:http://www.iop.org/activity/education/Teaching_Resources/Teaching%20Advanced%20Physics/Energy/Thermal%20physics/page_5417.htmlExternal referenceThis activity is taken from Advancing Physics chapter 13, 110SResources:http://www.myteacherpages.com/webpages/mbushway/files/Conduction-Convection-Radiation%20Power%20Point.ppt#2http://www.physicstutorials.org/index.php?option=com_content&view=article&id=166&Itemid=153http://www.howeverythingworks.org/clothing_and_insulation.html

Students-Define heat capacity and specific heat capacity of a substance.-Find the value for specific heat capacity of a solid or liquid.-Conclude that specific heat capacities of different solids and liquids are different.-Apply the concept of heat capacity in problem solving.Experiment: To measurespecific heat capacity of a metal

Post Content

AssessmentQuestions Worksheet given after each content based Activity-WorksheetQuestion Worksheet with solutions to the numerical given for the complete unit. More such numerical and questions may be framed by the teacher.

Parameter for assessment- learners can differentiate between-Different kinds of materials( on basis of shape, size, texture, state) Good and poor conductors of heat. Understand about specific heat capacityusing rubrics given in the scope

54 SCIENCE UNIT - 2

Steps to be followed Tools/ Activity used Description

Pre content Students are asked to tell about their knowledge of transfer of heat.

From their daily life experiences students tell about what are various ways of keeping things warm or cold. A brain storming about- is it that blankets generate heat or they do not allow heat to flow out and keep us warm on a cold winter day?

Content-1Finding the Best Insulation

Activity Worksheet 1- Annexure 21Teacher Support Sheet- Annexure Sample experiment 1A- Annexure23Sample experiment 1B – Annexure24 Video-http://www.youtube.com/watch?v=x77Z9UC1Fc4http://www.youtube.com/watch?v=cMmREKOhIV8&feature=relatedWeb Links:http://www.kids-science-experiments.com/insulators.htmhttp://www.worsleyschool.net/science/files/sciexperiment/page.hthttp://www.123helpme.com/view.asp?id=121685Questions Worksheet 1- Annexure

22

ml

25

An experiment where students take many coke cans and put hot water in each( same temperature). Wrap one in cotton wool, another in jute , 3rd in cotton fabric, 4th in a piece of some woollen fabric etc… but leave one without any cover. Note the temperature of each after regular time intervals / 20 minutes.

Content -2compare the rate of absorption of heat by different colours

Activity Worksheet 2- Annexure 26

Sample experiment 2A - Annexure 27

Teacher Support Sheet - Annexure28

Questions Worksheet 2- Annexure 29

Web Links:

http://www.juliantrubin.com/topicproje

cts/colorsprojects.html Resources

Gardner, Robert. Science Projects About

Light. Springfield, New Jersey: Enslow

Publishers, Inc., 1994, p. 92

Morton, J.L. Color Matters -

Electromagneic Color - 1995-1999

An experiment can be performed by taking 2 bottles with water. Note the temperature. Wrap one in white paper and one in black paper. Put both in the sun. Record the final temperature in both bottles after some time.

14 Lesson Template for UNIT 2:Materials: Section 2

55SCIENCE UNIT - 2

Steps to be followed Tools/ Activity used Description

Post Content Questions Given after every content based activity.Question worksheet given for the complete unit.

Parameter for assessment-Students understand and show application of their understanding for--Materials in our clothing-Clothes that are good insulators-Clothes that keep us cool ( white Vs Black clothes)-Cotton Vs synthetic fabricsBased on the rubrics given in the scope.

56 SCIENCE UNIT - 2

Annexure 1

This is a start up worksheet to check background knowledge.

Unit 2: Materials around us

Section-1

Worksheet 1

Learning Outcome:

The students will be able to:

Identify types of materials around them – wood, rocks, bricks, cotton wool, water,

oil, gases, soot etc

Observe that solids differ from each other in shape (crystalline, amorphous), texture

(smooth, rough, slippery, sharp), lustre, sonority, colour

Observe and understand that liquids differ in colour, smell, density, miscibility

with water and with other liquids, viscosity and volatility.

Observe and understand that gases differ in colour, smell, solubility in water, rate of

diffusion.

Classify each of the following material according to their physical states as learnt in previous

unit ‘Matter in our Surroundings’ and then further write what do you perceive about the

texture and appearance

G

G

G

G

15 Student and Teacher Support Materials

S.No. Material State Texture-rough/ Smooth/no

perception

Appearance Lusturous

/non-lusturous

Hardness- Soft/ hard/ no perception

i Charcoal Solid

ii Wood

iii Honey

iv Iron nail

57SCIENCE UNIT - 2

v Oxygen

vi Helium (filled in

balloons)

vii Vinegar

viii Silk scarf

ix Water Vapour

x Sand

xi Rubber sheet

58 SCIENCE UNIT - 2

Annexure 2

Teacher notes – Worksheet 1

This sheet can be used as a starter to the unit. The aim of this exercise is to allow students to

recall their experiences and appreciate the large variety of material present around us with

varied physical properties pertaining to their texture, shape, size, colour, floatation,

transparency, conduction, etc.

Once they have filled the coloumns in the given sheet, they should be given the opportunity to

check, as far as possible, their predictions. Where it is not possible to physically find the

properties students should be given the information by the teacher.

Many sheets can be created using this sample with different properties of magnetism,

conduction, transparency, floatation, sonority, viscosity, solubility in water etc. and students

may predict and then verify their predictions through self designed experiments.

59SCIENCE UNIT - 2

Annexure 3

Learning Outcome:

Kind of worksheet: Pre Content

UNIT II- MATERIALS

Section 1

WORKSHEET-2

Students should be able to identify types of materials around them based on their

characteristics.

AIM:

To discover the following characteristics of materials.

(a) Strength

(b) Flexibility

(c) Transparency

(d) Water proof

MATERIALS REUIRED:

A square sheet of each-a metal, paper, rubber, glass, and plastic. Water in a broad container,

hammer and test tube filled with coloured water

PROCEDURE:

1. Place the sheet of metal between two clamp stands

2. Perform one after the other following activity on it

(a) Try to press with your finger- observe if it bends or not for testing flexibility.

(b) Place a test tube having coloured water below it- observe if you can see the

test tube through the metal piece for testing transparency.

(c) Hammer the sheet- observe if it breaks or not for testing strength.

(d) Pour water on it- Observe water absorption capacity for testing water proof

property.

60 SCIENCE UNIT - 2

3. Similarly perform with all other materials taken.

OBSERVATION:

CONCLUSION:

Materials On pressing

with finger

On pouring

water

On

hammering

Seeing the test

tube through it

Metal

Paper

Rubber

Glass

Plastic

61SCIENCE UNIT - 2

Annexure 4

TEACHER SUPPORT SHEET

WORKSHEET-2

Background information:

The activity can be used by the student to discover the characteristics of different material

around them. Many other materials and many other properties can also be used in this

activity.

Observation expected:

Conclusion expected:

1. Metal- No flexibility, waterproof, strong and opaque

2. Paper – No flexibility, No strength, Water absorbent and opaque.

3. Rubber - flexible, waterproof, strong and opaque

4. Glass- No flexibility, No strength, waterproof and transparent

5. Plastic-No flexibility, waterproof, strong and opaque.

Characteristics of Materials

Materials have different properties that make them useful for different jobs. Here are some

properties that materials have.

1. Transparent or opaque: Transparent materials do let light through (you can see

through them). Opaque materials do not let any light through (you cannot see

through them).

Materials On pressing

with finger

On pouring

water

On

hammering

Seeing the test

tube through it

Metal No effect No effect No effect Can no see

Paper Breaks Soaks water Breaks Can not see

Rubber Bends No effect No effect Can not see

Glass No effect No effect Breaks Can see

Plastic No effect No effect No effect Can not see

62 SCIENCE UNIT - 2

2. Water proof: Waterproof materials do not let water through and do not soak up

water.

3. Strong: Strong materials are very difficult to break.

4. Flexible: Flexible materials are easy to bend.

5. Hard: Hard materials are difficult to scratch

6. Magnetic: Magnetic materials are attracted to magnets.

7. Conductors: Some materials are good conductors of heat. This means heat can

travel through them easily. Some materials are good conductors of electricity. This

means electricity can travel through them easily.

Classification of Materials

1. Metals:

Metals come from rocks called ores.They are strong, hard and shiny materials that can be

hammered into different shapes without breaking.Many metals are good conductors of

heat and electricity.Some metals are magnetic. Iron is the most magnetic metal. Steel is

also magnetic because it is made of mostly iron.Their properties make them useful for

objects such as cutlery, saucepans, cars and coins.

2. Plastics:

Plastics are materials that are not found naturally but are made from chemicals. They are

strong and waterproof, and can be made into any shape or colour. Many plastics can be

made transparent. They are not magnetic and do not conduct heat or electricity. Plastics

are used to make all sorts of things such as plastic bags, plastic bottles and toys.

63SCIENCE UNIT - 2

3. Glass:

Glass is made by melting sand.It is normally transparent and can be made into many

different shapes.Thick glass can be strong, but thin glass will break very easily.Glass is

used for objects that need to be transparent such as windows and spectacles.

4. Wood:

Wood comes from trees.It is strong, flexible and long lasting.Wood is used to make things

such as furniture that need to be strong and last a long time.

64 SCIENCE UNIT - 2

Annexure5

1. Why couldn't you use a plastic towel?

2. Why wouldn't you sit on a glass chair?

3. Where do metals come from?

4. Metal is used for nails because it...

5. Wood is used for matches because it ...

6.