Scientific Method/Measurements

An overview of scientific fundamentals

What is science?

• The word science comes from the Latin word scire “to know”.

• Science is a constant search to answer all the questions of the physical universe.

The Scientific Method (aka Inquiry)

• The Scientific Method- a step by step way to answer questions & solve problems.

• Steps of the scientific method– 1)State a problem– 2)Gather information (research)– 3)Form a hypothesis– 4)Test hypothesis (experiment)– 5)Record & analyze data– 6)State a conclusion

• * If hypothesis proves wrong you go back to step 3 & start again with a new hypothesis.

• **The problem must be clearly defined.

• Data can be gathered 2 ways. 1) Observation 2) Controlled experiments.

Hypothesis, Theory & Law

• Hypothesis – a proposed solution to a scientific problem. It is based on gathered information.

• Theory – a logical explanation of an event in nature. A theory must be testable. This is a little stronger than a hypothesis.

• Scientific Law – a theory that has been repeatedly tested & accepted as true.

• Even a law can be proven wrong over time.

Albert Einstein had many theories including Relativity

The Experimental Setup• Every experiment should have a variable

& a control.• Variable- The factor in an experiment being

tested. It can change in your experiment but nothing else can change. An experiment cannot give reliable results unless you test one variable at a time.

– The independent (manipulated) variable is the variable that you purposely change

– The dependent (responding) variable is what you observe to change as a result of your independent variable. This is what a scientist is trying to figure out.

• Control – an experiment done exactly the same as before but you leave out the variable. A control is done for the sake of comparison.

• Data – recorded observations & measurements. Data is best if presented in easy to read charts or graphs but can be written out freehand.

• *** A good conclusion should never be made without conducting the experiment more than once.

Sample Science Experiment• Dr. Maria Mattingly wonders if she can find a cure for

cancer. She goes to the archives at her lab and examines all the materials they have available and calls some colleagues at John Hopkins University who are also seeking a cure. She thinks that electrical shock treatments and Alka Seltzer combined can cure cancer. She gets 1000 cancer patients to volunteer and gives each 2 Alka Seltzer. Then she gives 250 patients 100 volt shocks. She gives 250 patients 500 volt shocks and she gives 250 patients 1000 volt shocks. She gives 250 alka seltzer only and pretends to shock them. She video tapes the process and documents each patient’s response and then interviewed each patient. She discovers that this technique does not work.

Section 2 Scientific Methods

Why Ask Why?

• Saving Lives Science helps make cars safer in many ways. These safety measures help save lives.

• Saving Resources Science helps make resources last longer through more-efficient methods of recycling.

• Saving the Environment Science helps protect the environment and makes the world a healthier place.

Section 1 Science and Scientists

Branches of Science

• There are 3 main branches off of the trunk that is science.

• 1.Life science (Biology)

• 2.Physical science• 3.Earth/Space

science• Many of the more familiar

fields of science are subbranches of these 3 main branches.

Scientists Are All Around You

• Meteorologist A meteorologist is a person who studies the atmosphere.

• Geochemist A geochemist is a person who specializes in the chemistry of rocks, minerals, and soil.

• Ecologist An ecologist is a person who studies a community of organisms and their nonliving environment.

Section 1 Science and Scientists

Scientists Are All Around You, continued

• Volcanologist A volcanologist is a person who studies volcanoes.

• Science Illustrator A science illustrator is a person who draws scientific diagrams.

Section 1 Science and Scientists

Section 2 Scientific Methods

Answer the following question: How can you prove that the world is not flat?

Write your responses in your science journal.

Bellringer

Measurement Systems• Experiments must use

measurements & these measurements should be reliable, accurate, & easy to communicate to others.

• There are 3 measurement systems commonly used today.

• 1.The Metric System (most common).2.The SI system (scientists) – it is almost he same as the Metric system

• 3.The English System – used only by USA and small African country.

Length

• Length- distance from one point to another.

• Long distances in space are measured in light-years. A light-year is the distance light can travel in one year. (AT LIGHT SPEED!)

1 lightyear = 9.4605284 × 1015 meters

Area

• Area- a 2 dimensional (2D) measurement. To find area of a surface you measure the length in 2 directions & multiply them.

• Area = Length X Width

Carpet or tile flooring requires an area measurement

Volume• Volume – the total space

an object occupies. Volume is a 3D measurement.

• Volume = Length X Width X Height.

• Volume of an irregular object can be found using Archimedes Principle (displacement of water).

Mass and Weight• Mass- the total amount of matter

in an object.(how many and what type of atom/molecule)

• Weight – the measure of attraction between objects caused by gravity. Mass X a gravitational constant.

• **** Mass & Weight are not the same. Weight depends on gravity.

• Ex On the moon you would weigh 1/6 what you weigh on Earth but your mass doesn’t change. This is due to less gravity on the moon.

Density

• Density – the amount of matter an object has for the space it occupies. (Mass per unit volume).

• Density = Mass/Volume

• Mass & Density have a direct relationship. (Mass ^ Density ^ , Mass v Density v ).

Volume & Density have an inverse relationship. (Vol. ^ Density v, Vol. v Density ^).

Temperature• Temperature - the

amount of thermal energy (heat) in an object.

• This is where the metric system & the SI system are different.

• All temperature scales are based on the freezing & boiling points of water

Temperature (cont.)

Scale Celsius Farenheight Kelvin

 

 Water

freezing pt

0 32 273

 

 Water

boiling pt

100 212 373

Zero degrees Kelvin is called absolute zero. At absolute zero all molecular motion theoretically ceases. (NO NEGATIVE TEMPERATURES)

System Metric SI English

Measures

Length Meter (+ prefix) Meter (+ prefix) Inches,feet,yards,miles

Area meter square (+ prefix) m2

meter square (+ prefix) m2

square English units ft2

Volume meter cubed (m3) or liter (+ prefix)

meter cubed (m3) or liter (+ prefix)

cubed English unit mi3

Mass gram (+prefix) Metric Ton

gram (+prefix) Metric Ton

Ounces, pounds, tons

Density grams/cm3 (prefix can change)

grams/cm3 (prefix can change)

a mass unit/ a volume unit

Temp. Celsius Kelvin Farenheight

Measurement System Comparisons

Bellringer

How would a standard system of weights and measures, agreed to and used around the world, make life easier? Give examples.

Write your answers in your science journal.

Section 5 Tools, Measurement, and Safety

Tools of the Scientist

• A scientist can use many tools depending on the field of study he/she is in.

• All fields of scientist use measuring tools, communication tools & computers.

Types of Scientific Models

• A representation of an object or a system is called a model or prototype.

• Physical Models look like they thing they represent. For example, the model flower shown at right can be used to learn the parts of a real flower.

Section 3 Scientific Models

Types of Scientific Models, continued

• Mathematical Models are made up of mathematical equations and data. The weather map shown below is a mathematical model.

Section 3 Scientific Models

Types of Scientific Models, continued

• Conceptual Models are systems of ideas or are based on making comparisons with familiar things to explain an idea.

• The big bang theory explains the origin of the universe. This theory is an example of a conceptual model.

Section 3 Scientific Models

Models Are Just the Right Size

• Models are often used to represent things that are very small or very large.

• Models are useful for studying cells and particles of matter that are too small to see with the unaided eye.

• Models are also useful for studying objects that are too large to see completely, such as the Earth or the solar system.

Section 3 Scientific Models

Section 3 Scientific Models

Bellringer

To teach cardiopulmonary resuscitation (CPR), instructors often use a mannequin to model a human upper torso and head. Why do you think CPR is taught with a model instead of a real human? Would the class be as effective if a model were not used? Explain your answer.

Section 4 Science and Engineering

What Is Technology

• Technology refers to the products and processes that are designed to serve our needs.

• Technology also refers to the tools and methods for creating these products.

• Technology applies to any product, process, or knowledge that is developed to meet a need.

Section 4 Science and Engineering

How Does Science Relate to Technology?

• Engineering uses scientific knowledge to develop technologies.

• Engineers use science and mathematics to create new technologies that serve human needs.

• There are many different types of engineers who develop a variety of very different products.

Section 4 Science and Engineering

How Does Science Relate to Technology? continued• Engineering is the process of creating technology.

• Scientists, inventors, business owners, artists, and even students have also engineered new technologies.

• Anyone can follow the engineering design process to solve a problem or address a need.

Section 4 Science and Engineering

What is the Engineering Design Process?

• The engineering design process has similarities to the scientific process.

• Like the scientific process, some steps may require repeating or modifying to fit different needs.

Section 4 Science and Engineering

What is the Engineering Design Process? continuedStep 1 Ask: Identifying and Researching a Need

• Engineers define and describe the need or problem they are trying to solve.

• Research provides engineers with information for problem solving.

Section 4 Science and Engineering

What is the Engineering Design Process? continuedStep 2 Imagine: Developing Possible Solutions

• Brainstorming is the process in which a group of people share ideas quickly to promote additional ideas.

• Sometimes a possible solution to the problem comes from these ideas or it may take more time and thought.

Section 4 Science and Engineering

What is the Engineering Design Process? continuedStep 3 Plan: Making a prototype

• A prototype is a test model of the product.

• Prototypes allow engineers to see if their design works the way they expect it to.

Section 4 Science and Engineering

What is the Engineering Design Process? continuedStep 4 Create: Testing and Evaluating

• Prototypes are tested and evaluated.

• Engineers complete a cost-benefit analysis to make sure that the cost of designing and producing the new product is worth its benefit.

• For example, it may only makes sense to produce a new product if it is not too expensive to produce.

Section 4 Science and Engineering

What is the Engineering Design Process? continuedStep 5 Improve: Modifying and Retesting the Solution

• If a prototype was not successful or did not work well, engineers would either modify their prototype or try a new solution.

• It is important that the engineers consider what was learned from the first prototype before they begin the design process again.

Section 4 Science and Engineering

Section 4 Science and Engineering

What is the Engineering Design Process? continued• Communication Engineers often need to share their successes, failures, and reasoning with others.

• Engineers may explain and promote the technology to customers, or they may communicate with the public through news releases, advertisements, or journals.

Section 4 Science and Engineering

Technology and Society

• Technology provides solutions for many types of social, political, and economic needs.

• Intended Benefit An intended benefit is the positive purpose for which a technology is designed to be used.

• Unintended Consequences Unintended consequences are uses or results that engineers do not purposely include in the design of products. An unintended consequence can be beneficial.

Section 4 Science and Engineering

Bioengineering

• Bioengineering The application of engineering to living things, such as humans and plants, is called bioengineering.

Assistive Technology (Device) – The term ‘assistive technology device’ means any item, piece of equipment, or product system, whether acquired commercially, modified, or customized, that is used to increase, maintain, or improve functional capabilities of individuals with disabilities. [Assistive Technology Act of 1998, S.2432] Adaptive Technology (Device) – An item that is specifically designed for persons with disabilities; devices which would seldom be used by non-disabled persons. [Glossary, Family Center on Technology and Disability]

Section 4 Science and Engineering

Bioengineering, continued

• Assistive Bioengineering Bioengineered technologies can be classified as either assistive or adaptive.

• Assistive technologies are developed to help organisms without changing them. Ex. Eye glasses, hearing aids, crutches, pacemakers, ect.

Adaptive bioengineered products change the living organism. Ex. Mechanical Limbs, cochlear implants, ect.

Prosthetics: Examples of Adaptive Technology