S3 CfE PhysicsMonifieth High School

Name:

Form Class:

Physics teacher:

In S3 Physics you will develop skills of literacy and numeracy as well as science skills in the context of six Physics topics:

Electronics p2

In this topic you will work through the science experience and outcome SCN 4-09b and SCN 4-09c.

• By contributing to investigations into the properties of a range of electronic components, I can select and use them as input and output devices in practical electronic circuits.

• Using my knowledge of electronic components and switching devices, I can help to engineer an electronic system to provide a practical solution to a real-life situation.

Exploring Space p9

In this topic you will work through the science experiences and outcome SCN 4-06a.

• By researching developments used to observe or explore space, I can illustrate how our knowledge of the universe has evolved over time.

Feel the force p15

In this topic you will work through the science experience and outcome SCN 4-08a.

• I can help to design and carry out investigations into the strength of magnets and electromagnets. From investigations, I can compare the properties, uses and commercial applications of electromagnets and supermagnets.

Need for speed p19

In this topic you will work through the science experience and outcome SCN 4-07a.

• I can use appropriate methods to measure, calculate and display graphically the speed of an object, and show how these methods can be used in a selected application. SCN 4-07a

Sound Engineering p24

In this topic you will work through the science experiences and outcome SCN 4-11a

• By recording and analysing sound signals, I can describe how they can be manipulated and used in sound engineering. SCN 4-11a

Shock and Awe p34

In this topic you will work through the science experience and outcome SCN 4-08a.

• Through investigation, I understand the relationship between current, voltage and resistance. I can apply this knowledge to solve practical problems.

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Electronics

How much of this do you think you can do?

before after

Give examples of electronic devices and systems

Name the three parts of an electronic system

Give examples of input and output devices

Know under which conditions input devices will give a logic 1/high/on output

Plan an investigation into how light level/temperature affects the resistance of a light/temperature sensor

Analyse data for a temperature/light sensor

Generate a conclusion linking temperature/light level and the resistance of a sensor

Present findings of an investigation into how light level/temperature affects the resistance of a light/temperature sensor

Give examples of process devices

Identify the symbols for AND, NOT and OR gates

Explain what these gates do

Select appropriate input and output devices for a specific design task

Select appropriate logic gates for a specific design task

Build an electronic circuit to fulfil a specific design task

Combine logic gates for complex design tasks

Draw truth tables for AND, NOT and OR gates

Explain what a truth table shows

Create truth tables for complex design tasks

2

No matter how complex electronic devices are they can be simplified down into three parts represented in this block diagram:

The first is “input” and these types of components are shown on the left hand side of the board below. The second part is “process” and examples of these are shown in the middle of the board. The process devices on this board are referred to as “logic gates”. The final part of the electronic system is an “output” component. The output components are shown on the right hand side of the board.

The temperature sensor is used in circuits where detecting temperature is important such as a thermostatically controlled central heating system. As the temperature of the sensor rises it’s resistance decreases. This causes a change in the signal given out from the input device that is being passed to the process device. When the sensor is warm it is described as given out a “logic 1” signal but when the sensor is cold it gives out a “logic 0” signal.

The light sensor is used in circuits where detecting light levels is important such as automatic street lights. As the light level falling on the sensor decreases it’s resistance increases. This also causes a change in the signal given out from the input device that is being passed to the process device. When the sensor is bright light it is described as given out a “logic 1” signal but when the sensor is in low light levels it gives out a “logic 0” signal.

The relay switch makes use of electromagnetism to close a switch in a remote circuit. The advantage of this is that almost any component could be connected in this additional circuit and could have it’s own power supply to run. In many cases it is useful to have an additional output device of a motor switched on by the relay switch.

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These logic gates can be combined together in different combinations with a variety of input and/or output devices to carry out specific jobs. Here is an example of a combined logic gate circuit design.

This circuit turns on central heating automatically when the system is turned on with the slide switch and the temperature in the room becomes low. The circuit makes use of a motor connected to the relay to operate the pump in the central heating system. The combined truth table for the circuit would be:

Temperature A F H Switch C J K N R SystemLow 0 0 1 On 1 1 1 1 1 OnLow 0 0 1 Off 0 1 0 0 0 OffHigh 1 1 0 On 1 0 1 0 0 Offhigh 1 1 0 Off 0 0 0 0 0 Off

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5

6

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19. (a) Plot a graph of this data collected for a temperature sensor.

Temperature (0C) Resistance (kΩ)10 6220 3430 1740 950 560 370 1

(b) What can you conclusion can be made from this data?

(c) What variables would need to have been controlled to make this data collection fair?

(d) What resistance would the temperature sensor have at 250C?

20. (a) Give an example of an electronic system.

(b) What are the input, process and output devices needed for the example you gave?

(c) Draw a truth table for the example you gave.

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Exploring Space

How much of this do you think you can do?

before after

Give examples of the impact that space exploration has had on my day to day life

Identify from a diagram different types of telescopes

Explain the difference between a reflecting and a refracting telescope

Identify the key parts of a refracting telescope

Explain how a refracting telescope works

Explain how a telescope can be used to identify planets in our solar system

State what is meant by an exo-planet

Explain how a telescope can be used to identify exo-planets

State what a planet needs in order to sustain life

State what is meant by the goldilocks zone

Explain why it is important for astronomers to look for exo-planets in the goldilocks zone

State an example of an exoplanet and describe how the exo-planet was discovered

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Exploring space using telescopes has allowed us to learn about the solar system, galaxy and universe in which we live. The technologies that have been developed for these telescopes have led to useful applications such as spectacles, contact lenses and digital cameras.

Optical telescopes (telescopes that collect light that we can see without eyes) use either lenses or curved mirrors to collect and focus light. A telescope that uses lenses is called a “refractor” because the light refracts (changes direction and speed) as it enters the lens. A telescope that uses mirrors is called a “reflector” because the light reflects from the mirror to a focus.

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Some telescopes such as the Hubble telescope orbit the earth outside of the atmosphere so that they can see a much clearer picture of the universe.

light received from a star or

Telescopes were used to identify the planets in our solar system. A planet can be distinguished from a star in the night sky as planets do not twinkle. The planet does not twinkle because it is large enough for eye to be able to see it as more than a point of light.

Telescopes can be used to identify planets out with our solar system. Planets that orbit stars other than our sun are called exo-planets. When a planet passes in front of a star the light from the star dims slightly. This effect can be used to identify exo-planets. Thousands of exo-planets have been discovered so far. As technology improves even more exo-planets are being discovered. Some of these are in our galaxy, the Milky way, others are even further away.

Astronomers think that some of these planets might be able to sustain life. If a planet it too close to a star it will be too hot to sustain life. If a planet it too far from a star it will be cold hot to sustain life. The distance from a star where the temperature is just right for a planet to sustain life is called the Goldilocks zone.

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1. Explain why astronomers want to explore the universe.

2. State an application of space exploration that you use in your life.

3. Describe the difference between a reflecting telescope and a refracting telescope.

4. Write an A4 newspaper article about the Hubble space telescope. Include the following points:

Who owns the telescope How much the telescope cost How the cost compares to other telescope How the cost compares to other things What the telescope has taught us about the universe Whether you think the cost of the telescope is worth it or not

5. Pick a planet within our solar systems and find out:

a. When it was discoveredb. Who discovered itc. What type of telescope they used

6. State what is meant by an exo-planet.

7. Explain how astronomers can detect exo-planets.

8. Describe what is meant by the term “Goldilocks zone”.12

9. An astronomer measures the brightness of a distant star for 2 years.

The data is shown in the table below:

Date of data collection Brightness of star (Lux)

January 2012 5

April 2012 4

July 2012 3

October 2012 2

January 2013 3

April 2013 4

July 2013 5

October 2013 4

a. Plot a graph of the data collected by the astronomer.b. What brightness does the astronomer measure in September 2013?c. Predict the brightness the astronomer would measure in January 2014?d. Sketch a line on the graph to show what data the astronomer would expect for a second planet

which is closer to the star.

10. Read the newspaper article opposite so that you can answer the following questions.

a. What is certain in this article?

b. What is uncertain in this article?

c. What science is the article based on?

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Visiting astronaut Colonel Alvin Drew on the future of man in space

On February 28 this year, Colonel Alvin Drew became the 200th man to walk in space. Currently in Dundee to receive an honorary degree from Abertay University and deliver a public lecture, the American astronaut told Jack McKeown about the future of space exploration.

Alvin Drew was a child when America took its first steps into space. Aged seven he watched, transfixed, as Neil Armstrong stood on the surface of the moon. "That was over 40 years ago," he smiles. "The space age really is in the past, we're in the digital age now. In fact, there's a bit of a disconnection between the older and the younger generation of scientists at NASA. "The younger ones are saying 'we need wireless technology in the shuttles'. And the older ones are saying 'we got to the moon without any of that stuff'."

Born in Washington DC, Alvin (48) joined the US Air Force in 1984 and fought in the first Gulf War.

He joined NASA in 2000. "It was a childhood dream," he says. "But it was never one I expected to become reality. I'd filled out the application form — it was like War and Peace — and a couple of months later a little postcard came through my door. "I thought it was a rejection letter, but it told me to report to NASA for an interview."

Alvin spent the next five years training. "A lot of the time you're waiting in a queue for the facilities. The pool we use for space walk training is about 40 feet deep and half the size of a football pitch. It costs about $1000 a minute to run. "All of the simulators are incredibly realistic. We had to negotiate a shuttle into space and back to Earth again, and of course all sorts of things went wrong — parts seized up, there were fires. When we successfully completed the mission, we felt about 11 feet tall."

After years of training, Alvin left the Earth's atmosphere for the first time in August 2007 aboard the space shuttle STS-118, on a 13-day mission to re-supply the International Space Station. "Because the International Space Station doesn't self-generate, we have to bring up all the food, air, water and clothing. "We brought up 2.5 tons of equipment to the space station and remove the same amount of waste to return to Earth."

"Our training is very realistic so everything felt strangely familiar. But you have to really focus because it's easy to get distracted by passing over an aurora borealis or a shooting star." Surprisingly, Alvin plans to step away from space travel, temporarily at least, to help design the next generation of space shuttles. "I've been into space and now it feels like time to help build the vessels that the astronauts of tomorrow will fly in. "If they're going to go to Mars we need to build the shuttle that's going to carry them there."

Alvin is in Dundee all week to receive an honorary degree, teach children at Abertay Space School and deliver a public lecture. "Meeting the kids at the Abertay Space School has been incredibly humbling."They are so smart and switched on. They made a board game showing what an astronaut does over a day. It took me years of training to learn and they have it nailed in an afternoon. It's incredible."

http://www.thecourier.co.uk/News/Dundee/article/15438/visiting-astronaut-colonel-alvin-drew-on-the-future-of-man-in-space.html

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Feel the Force

How much of this can you do?

before after

Explain if magnets work in space or not

Explain what a magnetic field is

Explain how a magnetic fields can be shown to exist

Draw the magnetic field lines around single magnets and magnet combinations

15

Use the words attract and repel to explain the interactions between magnets

Give examples of what the strength of a magnet depends on

Justify and report on the choice of magnet made

Explain what an electromagnet is

Build an electromagnet

Give examples of what the strength of an electro magnet depends on

Give some uses of magnets/supermagnets/electromagnets

Choose the right magnet for a specific job

Explain how some uses of magnets/supermagnets/electromagnets work

Magnets can work anywhere! They can work under water, in jelly and even in outer space. This because the magnetic field that surrounds them does not need particles or gravity to interact with other magnetic fields. A magnetic field is an area around a magnet were magnetic force can be felt without having to touch the magnet. Although these fields are invisible to our eyes they can be shown to exist using iron fillings. These iron fillings line up along the fields lines of the magnetic fields. The closer together these lines are the stronger the field is. These diagrams show the magnetic field lines around magnets:

Different magnets have different strengths. The strength of the magnet can depend on its size, how heavy it is and its shape but mostly on the material that it is made from. Alinco (usually red magnets) are reasonably week whilst ceramic magnets) usually grey are a bit stronger. The strongest paramagnet magnets are made from neodymium (these are often silvery in colour) are often referred to as super magnets. Permanent magnets have a lot of uses in children’s toys and for magnetic breaking.

There are some disadvantages to permanent magnets. The magnetic fields of permanent magnets

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Alnico permanent magnet Ceramic Ferrite

permanent magnet

Neodymium permanent magnet

can not be turned off were as the fields on an electromagnet can be turned on and off. This means an electromagnet can be used to lift objects up to move them and then drop them easily. An electromagnet is made by passing electricity through a coil of wire which has been wrapped around an iron core. The more electricity is passed through the wire and the more times that the wire is coiled around the core the stronger the electromagnet will be.

Both permanent and electromagnets can be used in applications to attract (pull towards) certain metals (usually those containing iron). This property is used in applications such as the solenoid inside car central locking systems and automatic doors, automatic relay switches, circuit breakers, electric motors in fans and washing machines and in electric bells.

Magnets can also be used in applications to repel (push away) other magnets. If two magnets have the same poles pointing towards each other (for example two north poles) then the magnets will repel. If two magnets have opposite poles pointing towards each other (for example one south and one north pole) then the magnets will attract. This property of attraction and repulsion of poles is used in compasses to line up with the earth magnet fields and direct explorers towards north, in maglev trains, in headphones, in loudspeakers and in computer hard disks.

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1. a) Name the two poles of a magnet

b) In which of these situations would the magnets repel:

2. Draw the magnetic field pattern around:

a) single bar magnet

b) two bar magnets being attracted to each other

c) two bar magnets repelling each other

3. a) Plot a graph of this data collected for an electromagnet:

Electrical Current (A) Pulling Force (N)1 0.6

1.5 0.82 1.33 1.7

3.5 2.14 2.35 3.1

b) What can you conclusion can be made from this data?

c) What variables would need to have been controlled to make this data collection fair?

d) What current would need to be supplied to this electromagnet to provide a force of 2.5N?

4. a) List the equipment that you would need to make a working electromagnet.

b) Draw a diagram to show the set-up of the electromagnet.

c) How could the strength of the electromagnet be increased?

5. a) Give an example of a use of magnetism/electromagnetism.

b) Explain how the example you gave works.

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situation 1 situation 2

N N N S

6. Process the information in this pie-chart into a table showing the same information.

Aluminium Nickel

Cobalt Iron

7. Write a summary describing what this bar chart shows.

Alnico Ferrite Neodynium SMM0

5

10

15

20

25

30

35

40

19

12%

26%

24%

38%

% Iron in make up of Magnet materials

The Need For Speed

How much of this do you think you can do?

before after

Measure the average speed of an object

Carry out calculations using the relationship between time, distance and average speed

Measure the instantaneous speed of an object

Carry out calculations using the relationship between time, distance and instantaneous speed

Explain the difference between instantaneous speed and average speed

Explain the term acceleration

Carry out calculations using the relationship between time, acceleration and change in instantaneous speed

Measure the acceleration of an object

Explain the difference between speed and acceleration

Give examples of everyday speeds and accelerations

Give examples of jobs that require an understanding of speed and acceleration

Design, build test and modify a model rocket car

Explain how cars can be brought safely to a stop

Describe speed-time graphs for vehicles accelerating, travelling at a constant speed and decelerating

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Speed is the distance travelled by an object in one second (usually expressed in meters per second or m/s or ms-1).

The average speed ( v ) of an object is the average for the whole journey. To calculate average speed the distance travelled can be measured with a ruler and the time taken to travel the distance can be measured with a stop clock.

The instantaneous speed ( v or u) of an object is its speed at one particular point during the journey. To calculate instantaneous speed the length of card is measured with a ruler and the time taken for the card to pass through a light gate is measured with an electronic timer.

The acceleration of a vehicle is how much its speed changes each second. Acceleration is usually measured in meters per second per second (m/s/s or m/s2 or ms-2). Acceleration can be calculated by dividing the change in speed by the time taken for the change.

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When a trolley runs down a slope in the classroom its average speed will be around 0.2m/s and its maximum instantaneous speed will be about 0.5m/s. In a built up area traffic is limited to maximum instantaneous speeds of 30mph which is about 15m/s. On motorways most vehicles are limited to 70 mph which is about 35m/s.

distance

speed =

d

v =

v- u

a =

time t

t

The Bloodhound Project is made up of a team of scientists and engineers attempting to create the ultimate Land Speed Record car. The target is to reach an average speed of 1,000mph (about 500m/s) over two fixed distances. One distance is a mile (1,600m) and the other is a kilometer (1,000m). The cars speed increases at about 60mph every second achieving a maximum acceleration of 25m/s2. The car however can not stop in a distance less than 4.5 miles (7,242m). This is about the distance from Monifieth High School to the Odeon cinema in Dundee! You can find out more at www.bloodhoundssc.com.

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1. Explain the difference between measuring average and instantaneous speed.

2. In an experiment to measure instantaneous speed, these measurements were obtained:-

Time on light gate = 0.125 s

Length of car = 5 cm

(a) Can these values be used to calculate average or instantaneous speed?

(b) Calculate the speed of the vehicle in m/s.

3. Describe how you would measure the acceleration of a small vehicle as it runs down a slope in the laboratory.

4. A car reaches 30 m/s from a speed of 18 m/s in 6 s. What is its acceleration?

5. Copy and complete:

Starting speed

(m/s)

Final speed

(m/s)

Acceleration

(m/s/s)

Time

(s)

0 15 (a) 5

30 10 (b) 5

0 18 6 (c)

0 (d) 9 3

(e) 32 4 7

6. Explain the difference between the terms speed and acceleration

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7. Calculate the acceleration of these vehicles in m/s/s:

8. Use the graph below to answer the following questions.

(a) During which time is the vehicle travelling at a constant speed?

(b) Calculate the values of

(i) the initial acceleration

( ii) the final deceleration

9. In your view is it worth trying to build a car that can reach 1000mph? Explain and justify your view.

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Sound Engineering

How much of this do you think you can do?

before

after

Explain what sound is with reference to the movement of particles.

Explain different ways that sound is transferred.

Describe a method for measuring the speed of sound in air.

Explain what effects the rate at what sound travels through a medium.

Explain what a sound level meter is, how it works and state its applications.

Define the term decibel (dB) and use it to explain noise levels.

State the sound level of a given situation.

Define the term frequency.

State the relationship between pitch and frequency.

State the human range of hearing.

Identify between transverse and longitudinal waves.

Identify and label parts of a wave.

Explain how the ear operates and allows us to hear.

State that sound is a longitudinal wave.

State that the amplitude of a wave is directly proportional to the amount of energy a wave has.

Explain the function of an amplifier.

Identify and draw the circuit symbol for an amplifier.

Explain what sounds interference is.

Describe the two forms of interference: constructive and destructive.

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Our ears are sensitive to tiny fluctuations in air pressure that are created by vibrating particles. The fluctuations and the sensations they produce in our ears are called sound.

Sound travels in waves, spreading out from its source like ripples on a pond. The stronger the motion of the source, the louder the sound. The faster the source vibrates, the higher the frequency or pitch.

The average speed ( v ) of an object is the average for the whole journey. To calculate average speed of sound in air the distance travelled can be measured with a trundle wheel and the time taken to travel the distance can be measured with a stop clock.

The speed of sound is the distance travelled during a unit of time by a sound wave propagating through a medium. In dry air at 20 °C the speed of sound is 343.2 metres per second. This is 1,236 kilometres per hour (768 mph), approximately one mile in five seconds. Mach number is a quantity representing the ratio of speed of an object moving through air and the local speed of sound.

Sound can be transferred any time particles are given energy to move. This could be done by plucking a string, chapping a table or carefully controlling a stream of air through a small hole, better known as whistling.

As sound can be produced by transferring energy from one particle to another, then an object with more particles close together will be able to transfer its energy quicker and more efficiently.

The speed of sound in wood ≈ 3500ms-1

The speed of sound in water ≈ 1500ms-1

The speed of sound in air ≈ 340ms-1

A vacuum is a volume of space that has evacuated all of the particles that occupied it. With no particles to transfer energy, there can’t be any sound. The 1979 film Alien famously had the caption “In space no one can hear you scream” on its advertisement posters. A bell jar and pump are scientific tools that can create a vacuum.

A sound level meter or sound meter is an instrument which measures sound pressure level, commonly used in noise pollution studies for the quantification of different kinds of noise, especially for industrial, environmental and aircraft noise. The decibel (abbreviated dB) is the unit used to measure the intensity of a sound. The decibel scale is a little odd because the human ear is incredibly sensitive. Your ears can hear everything from your fingertip brushing lightly over your skin to a loud jet engine. In terms of power, the sound of the jet engine is about 1,000,000,000,000 times more powerful than the smallest audible sound. That's a big

difference! A decibel is one tenth of a bel, a seldom-used unit named in honour of Alexander Graham Bell.

In Physics, frequency is the number of occurrences of a

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distance

speed =

d

v = time t

repeating event per second (per unit time). Just like time has the unit seconds (s), frequency has the unit Hertz (Hz) named after Heinrich Hertz. A frequency of 200Hz means that 200 events happen each second.

Pitch is an auditory sensation in which a listener assigns musical tones to relative positions on a musical scale based primarily on the frequency of vibration. Therefore, as the frequency of a source increases, so does the pitch.

Hearing range usually describes the range of frequencies that can be heard by an animal or human, though it can also refer to the range of levels. In humans the audible range of frequencies is usually 20 to 20,000 Hz, although there is considerable variation between individuals, especially at high frequencies, where a gradual decline with age is considered normal.

Longitudinal wave:

The length of a wave – the wavelength, is denoted by the Greek letter Lambda, λ and is measured in metres (m).

A compression is a space that has a lot of air particles squeezed close together, high pressure regions.

A rarefaction is a space that has very few particles close together, low pressure regions.

Sound is an example of a longitudinal wave.

Transverse wave:

The crest of a wave is the point of maximum height reached by a wave.

The trough of a wave is the point of lowest point reached by a wave.28

λDirection of movement of energy

Movement of

Peak / crest

Trough

Amplitude Wavelength

The length of a wave – the wavelength, is denoted by the Greek letter Lambda, λ and is measured in metres (m).

The maximum distance from the midpoint to a crest or trough - the Amplitude, is denoted by the letter A and can be measured in any unit of length. The amplitude of a wave is directly proportional to the amount of energy a wave has. The greater the amplitude, the louder the sound.

Light is an example of a transverse wave.

Sound waves are longitudinal and travel into the ear canal until they reach the eardrum. The eardrum passes the vibrations through the middle ear bones or ossicles into the inner ear. The inner ear is shaped like a snail and is also called the cochlea. Inside the cochlea, there are thousands of tiny hair cells. Hair cells change the vibrations into electrical signals that are sent to the brain through the hearing nerve. The brain tells you that you are hearing a sound and what that sound is.

Each hair cell has a small patch of stereocilia sticking up out of the top it. Sound makes the stereocilia rock back and forth. If the sound is too loud, the stereocilia can be bent or broken. This will cause the hair cell to die and it can no longer send sound signals to the brain. In people, once a hair cell dies, it will never grow back. The high frequency hair cells are most easily damaged so people with hearing loss from loud sounds often have problems hearing high pitched things like crickets or birds chirping.

The Amplifier:

The electrical symbol for an amplifier:

A good music system has to be able to amplify all ranges of frequencies by the same amount, this is tricky and if done poorly can cause distortion. Songs have a range of frequencies occurring at once. Using a Marshall amplifier we can see what effect amplifying different frequency ranges – bass (20-300Hz) and treble (higher frequencies) of sound has on the overall sound of a song. Interference:

In Physics, interference is a phenomenon in which two waves interact and a new wave is produced.

There are two types of interference:29

Constructive Destructive

Constructive interference:

The two waves that are interacting together are “in phase”.

Destructive interference:

The two waves that are interacting with each other are “out of phase”

The speed of sound can also be calculated from the wavelength and frequency of the sound wave:

V = speed in m/s

f = frequency in Hz

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V = f λ

λ = wavelength in m

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1. The following apparatus was set up to measure the speed of sound:

(a) Describe how you would use this apparatus to measure the speed of sound.(b) If the distance between the hammer and microphone was increased, would this give

you a more accurate or less accurate result? Explain your answer.

2. Physics teacher, Paul, is waiting at the green of the 18th hole at Palacerigg golf course. He sees his friend, Danny, about to tee off. The tee is 436 metres away from Paul, who quickly decides that this would be a perfect opportunity to measure the speed of sound. Luckily his mobile phone is equipped with a stopwatch.

(a) Describe how Paul measures the speed of sound on the golf course.(b) Explain whether or not you think he will get an accurate result.

3. What is the speed of sound in air in m/s?

4. Calculate how far sound travels in:

(a) 1 second (b) 3 seconds (c) 10 seconds.

5. The diagram below represents the particle arrangement for an ice cube (solid) changing to water (liquid) then steam (gas).

By thinking about the arrangement of the particles, do you think sound will travel fastest in a solid, or liquid or gas? Explain your answer.

6. What do waves carry?

7. What are the 2 types of waves?

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8. Look at the diagram below and answer the following questions.

(a) What type of wave is this?(b) The wave is moving from left to right. Describe how point X on the wave is moving.

9. A “slinky” can be used to show different types of wave.

(a) What type of wave is the “slinky” showing here?(b) The wave is moving from left to right. Describe how point X on the wave is moving.

10. Copy and complete the following sentences:

_________________ waves, for example water waves, carry __________ by vibrating at right angles to the direction of the wave’s motion._________________ waves, for example sound waves, carry _________ through a _____________ where the particles vibrate in the _____ direction as the wave’s motion.

11. ‘A-B’ represents one wavelength in the diagram below.

State two other pairs of letters which represent one wavelength.

12. The wavelength of the waves in the diagram below is 3 cm. What is the distance between X and Y?

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Direction of oscillations

13.

(a) How many waves are shown in the diagram above?(b) What is the wavelength of each of these waves?(c) What is the amplitude of these waves?

14. If a wave machine produces 5 waves each second what is the frequency of the machine?

15. A man stands on a beach and counts 40 waves hitting the shore in 10 seconds. What is the frequency of these waves?

16. Some sound waves have a frequency of 10 000 Hz. How many of these waves will be produced in 100 seconds?

17. A tuning fork makes a sound with a frequency of 440 Hz. How long does it take to produce 2 200 waves at this frequency?

18. Look at the oscilloscope trace below, which represents a sound from a keyboard.

(a) Draw the trace that would be obtained if a note of higher pitch but same volume was played.

(b) Draw the trace that would be obtained if the same note was played at a louder volume.

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19. Use the following table of information to answer the questions below.

(a) What is the approximate sound level of a whisper at a 2 m distance?

(b) What produces a sound level of 100 dB?

(c) Why is the sound level of 90 – 95 decibels so important?

(d) Explain why ear protection should be worn if operating a hand drill for a prolonged period of time.

20. Noise cancellation technology is used in headphones worn by helicopter pilots.

Why is this useful?

21. Sounds can be reflected and absorbed. In a sound proofed recording studio, the walls are covered in material to prevent sound escaping from the studio.

Should this material be a good absorber or a good reflector of sound? Explain your answer.

22. State the frequency range of human hearing.

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Sound Levels for Various Environmental SoundsWeakest sound heard 0dBWhisper Quiet Library at 2 m 30dBNormal conversation at 1 m 60-65dBTelephone dial tone 80dBCity Traffic (inside car) 85dBTrain whistle at 500', Truck Traffic 90dBLevel at which sustained exposure may result in hearing loss 90 - 95dBHand Drill 98dBSnowmobile, Motorcycle 100dBSandblasting, Loud Rock Concert 115dBPain begins 125dBPneumatic riveter at 1 m 125dBEven short term exposure can cause permanent damage - Loudest recommended exposure WITH hearing protection 140dB

Jet engine at 30 m 140dBDeath of hearing tissue 180dBLoudest sound possible 194dB

23. Read the news article below then answer the questions that follow.

Environmentalists in Peru are warning that an unprecedented number of dead dolphins are washing up on the country's shores because of the use of deep water sonar systems by the shipping industry.It follows the discovery of 615 of the mammals in the last few weeks along a 135 kilometre stretch of coastline. As many as 3,000 dead dolphins have been found since the beginning of Peru's summer.

Researchers at the Organisation for the Conservation of Aquatic Animals (ORCA), a Peruvian marine animal conservation organisation, said that ships using deep water sonar are to blame for the mass deaths.

After studying the corpses of many of the dolphins, it was noticed that they did not bear marks of external damage caused by fishing practices or signs of poisoning. Instead, researchers found damage in the dolphins' middle ear bones, which is said to be a sign of decompression syndrome. "We have been noting that the animals were suffering from acute decompression syndrome - that is to say, a violent death produced by an acoustic boom that disorients the animal and produces haemorrhages which cause the animal to end up dying on the beach," said ORCA director Dr Carlos Yaipen.

The damage is said to come from sonic bursts that are produced by deep water sonar signals sometimes used in the search for petroleum. US federal regulators are curbing an oil and natural gas exploration company from using seismic equipment that sends out underwater pulses along Louisiana's coast until the bottlenose dolphin calving season ends.

ORCA calculates that the phenomenon represents the highest number of beached dolphins recorded anywhere in the world in the last decade

(a) For what does “ORCA” stand?(b) How many dead dolphins have been found since the beginning of Peru’s summer?(c) What evidence did the researchers at ORCA have to suggest that deep water sonar was to blame for the death of the dolphins?(d) What action has been taken elsewhere in order to protect dolphins from the impact of sonar?

24. Sound of frequency 440 Hz has a wavelength of 3·41 m in water. Calculate the speed of this sound in water.

25. Water waves in a swimming pool are travelling with a speed of 2 m/s and have a wavelength of 0·8 m. What is their frequency?

26. A wave generator in a ripple tank creates waves which have a wavelength of 0·02 m. If the speed of these waves is 1·2 m/s what is their frequency?

27. The musical note ‘E’ has a frequency of 320 Hz. If sound travels with a speed of 340 m/s in air calculate the wavelength of this sound in air.

28. Calculate the frequency of the waves shown in the diagram below given that they have a speed of 0·05 m/s.

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5cm

Shock and awe

How much can you do?

before after

Know common electrical symbols for lamps, wires, switches, cells, batteries, ammeters, voltmeters, resistors and variable resistors.

Know that current is a flow of electrons.

Apply an understanding of current to explain the rules for current in series and parallel circuits.

Know that current is measured in amperes (A) using an ammeter that must be connected in series into the circuit.

Know that a voltage is a measurement of the energy given to move the electrons around a circuit.

Apply an understanding of voltage to explain the rules for current in series and parallel circuits.

Know that a voltage is measured in volts (V) using a voltmeter in parallel with the component.

Explain what is meant by the term resistance.

Give examples of factors that affect resistance.

Know that the unit of resistance is the ohm ().

Covert between k and .

Know that if the supply voltage to a fixed resistance circuit doubles the current through the circuit doubles.

Know that for fixed resistors, the resistance remains approximately constant for different currents.

Know that as the resistance of a variable resistor increases the current through it decreases.

Know that as the resistance of a variable resistor increases the voltage across it increases.

Perform calculations using ohm’s law.

Convert between mA and A and between kV and V.

Give two practical uses for variable resistors.

Use your understanding of resistance to design circuit to solve problems.

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Measuring Current.

Current is measured in Series.

Current is measured by inserting into the circuit.

Current is a measurement of flow of electrons.

Current is measured in Amperes, Amps for short (A).

Ohm’s Law.

V = IR

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Current (A)

Resistance (Ω)Voltage (V)

Measuring Voltage.

Voltage is measured in Parallel

Voltage is measured by adding outside the circuit

Voltage is the measurement of the energy of the electrons

Voltage is measured in Volts (V)

Summary of a series circuit.

Summary of a parallel circuit.

Circuit applications.

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1a. Give an example of a use of electricity in the economy.

1b. Explain how the need for electricity impacts on society in large.

2a. What is an electrical current?

2b. What is used to measure an electrical current and how is it connected into a circuit?

2c. In what units is electrical current measured?

2d. Draw a circuit diagram to show how the current through a bulb could be measured.

3a. What is voltage

3b. What is used to measure voltage and how is it connected into a circuit?

3c. In what units is voltage measured?

3d. Draw a circuit diagram to show how the voltage across a bulb could be measured.

4a. Plot a graph of this data collected for a resistor

Voltage (V) Current (A)

0 0

1 0.14

2 0.31

3 0.46

4 0.58

5 0.77

6 0.93

4b. What can you conclusion can be made from this data?

4c. What variables would need to have been controlled to make this data collection fair?

4d. What current would be read from the ammeter if a voltage of 13V was accidentally applied across the resistor?

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5a. State Ohms law.

5c. Use Ohms law to calculate the missing values in this table:

Voltage (V) Current (A) Resistance ()

(a) 15 35

(b) 230 125

(c) 120 12

6a. How many Amps is 0.1mA?

6b. How many Volts is 13kV?

6c. What current flows through a 20 kΩ Monkey struck by a 500V lightning bolt?

7a. What is resistance?

7b. State three factors that affect resistance and if they increase or decrease resistance.

7c. Describe an application of resistance.

8a. Draw a circuit diagram to show how the resistance of a variable resistor could me determined?

8b. What happens to the current in the circuit as the resistance of the variable resistor increases?

9a. Two bulbs are connected to a supply as shown. What is the voltage of the cell?

9b. Two resistors are connected in series to a supply as shown in the diagram.

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0.001 m

As Current (A)

10. A rheostat is used as a dimmer switch in a series circuit as shown.

The rheostat is adjusted until the bulb is shining brightly. The voltage across the bulb is 13·8 V and the current through the rheostat at this setting is 1·7 A.

(a) Calculate the voltage across the rheostat.

(b) Determine the current flowing in the bulb.

11. Two resistors are connected in parallel to a 12 V battery.

(a) Determine the voltage across R1.

(b) Determine the voltage across R2.

(c) Calculate the current drawn from the battery.

12. Two identical bulbs and a resistor are connected in parallel to a 6 V supply.

(a) Determine the voltage across L2 .

(b) A current of 1·8 A flows through each of the bulbs. Calculate the current flowing through the resistor.

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Resistance ()

12 VR2

14 V

200

100

The

15 V 2·5 V

4.5 V

Vol

Notes:

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Notes:

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How to revise for a Physics test!1. Evaluate progress

At the start of each topic there is a list of things that you need to be able to do. Use that list to work out what you can and can’t do.

2. Work on knowledge

There will be some things that you need to memorise from the topic like the meaning of symbols in formula (e.g I means current) and what units quantities are measured in (e.g current in measured in Amps). Different people memorise in different ways you could try:

• Flash cards• Cover copy check• Stickies around your room

3. Work on understanding

There will be things that you will need to describe or explain like how to measure the speed of sound in air. These are ways to help improve your understanding:

• Summarising your notes in your own words• Making a mind map to show how ideas are connected together

4. Work on problem solving

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Problem solving involves applying your understanding to things that you have not seen before. You might have to do things like carry out calculations or make suggestions to improve experiments. Dong and re-doing Homework questions can help you improve your problem solving skills.

Find out what careers Physics can help you with at www.physics.org/careers

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