Module P1. Homework: Higher demand.
Eight Weeks of homework to be handed in on A4 paper, handwritten neatly. All answers can be
found on the website www.revisegcsephysics.co.uk
1a: Heating Homes [Due the Monday after Easter holiday]
1. What happens to the temperature of an object that is hotter than its environment( the immediate
surroundings) when left alone? Why does this happen?
2. What happens to the temperature of a cold object when left alone? What conditions are required
for the temperature of the object to change? Why does this happen?
3. What determines the rate at which an object heats up or cools down?
4. An ice cube will make your skin feel colder. Which direction has the cold moved in?
5. Why does a metal fork feel colder than a plastic spoon, even though both are at room
temperature?
6. What happens to the amount of energy contained in an object when the object is heated?
7. What is thermal energy?
8. What is heat?
9. What is the difference between thermal energy and heat?
10. Will an objects temperature continue to rise as long as it is heated? Explain what happens.
11. If an object’s temperature is well below it melting point temperature, and it is being heated,
what would cause the object’s temperature to not rise?
12. What is a thermogram?
13. Which colours represent the hotter and the colder parts of an object on a thermogram?
14. What are the units of energy? Name and symbol.
15. What does it mean if some physical quantity is measured in Joules?
16. What three factors determine the amount of energy that is required to raise the temperature of
an object by a specified amount?
17. Write down the equation for specific heat capacity of a material.
18. What value of temperature should be used in a calculation of specific heat?
19. What does the amount of thermal energy in an object depend upon? Three parameters.
20. Which has more thermal energy a bathtub of water at 45 degrees or a tea cup of coffee (!?) at 90
degrees?
21. Which way does the heat energy flow in the above example, if the bathtub and teacup are
brought into contact with each other?
22. What does a higher rate of heating or cooling mean?
23. Define temperature. Include a reference to the average kinetic energy of the particles.
24. What is the difference between an absolute and an arbitrary (or chosen) scale of measurement?
25. Which type of scale are heat and temperature measured on?
26. What is meant by ‘a change of state’?
27. What happens to the temperature of a substance as it is heated or cooled past its boiling or
melting points? Why does this happen?
28. What is the specific latent heat of an object? Write an equation for latent heat capacity.
29. Correct the following spelligs: sbisifik heet capasity, temprature, ferrmogram.
30. Explain what happens during heating, cooling, boiling and melting using the terms - heat flow,
thermal and latent energy changes each time. 4 parts to the answer.
P1b Keeping homes warm. [Also due the Monday after the Easter Holiday]
1. Explain why trapped air in a material is a very good thermal insulator.
2. What do ‘good thermal conductor’ and ‘good thermal insulator’ mean and how are these two
terms related?
3. What type of surface reflects infrared radiation?
4. What happens to infrared radiation on a dull or rough surface?
5. List four ways to save energy in the home (related to heating homes only).
6. Explain how the fact that air is a very good insulator is used in the four following methods of
keeping home warm: i) fibreglass, mineral or rock wool in loft insulation, ii) double glazing in
windows, iii) insulation foam or fibreglass in cavity walls and iv) curtains at windows.
7. Explain how reflective foil in or on walls helps to keep home warm.
8. Explain how draught-proofing works to keep a home warm.
9. Write down the equation for efficiency of energy conversion.
10. If one 1000 joules electrical energy are used by an electric heater to produce 800J of heat, what
is the efficiency of the heater as a percentage?
11. Explain how energy is transferred by each of conduction, convection and radiation.
12. Why are metals very good conductors of heat?
13. What types of materials (states of matter) are present when conduction, convection and
radiation occur?
14. Explain which modes of heat transfer (conduction, convection or radiation) are prevented by
each of i) Loft insulation ii) double glazing iii) cavity wall insulation.
15. Explain what is meant by i) a heat source, and ii) a heat sink.
16. Saving energy and cost of fuel bills often requires purchasing improvements to improve the
insulation of a house. Explain what is meant by i) initial cost ii) annual saving on energy bills
iii) payback time.
17. Describe what a Sankey diagram is, with an example.
18. Explain how the design of a home can be improved to reduce energy losses by conduction,
convection and emission of radiation.
19. Explain how homes can be designed to improve or reduce absorption of radiation.
20. Explain how the design and use of everyday appliances must consider convection conduction
and radiation.
21. Convert the following percentages to ratio terms. i) 30% , ii) 55%, iii)75%
P1c, A spectrum of waves. [Due Mon19th of March]
1.
Explain, with diagrams, the main difference between transverse and longitudinal waves.
2.
Give examples of both transverse and longitudinal waves. Include light and sound.
3.
Draw a sine wave and label the diagram using arrows with trough, crest, amplitude and
wavelength.
4.
What is the speed that electromagnetic waves called and what is its value.
5.
Write down the wave equation.
6.
Define the following terms: speed, frequency, wavelength and amplitude.
7.
Explain the law of reflection.
8.
Explain what is meant by refraction of a wave.
9.
Complete the following diagram for reflection and refraction of a light wave.
10.
What happens to the speed and direction of a wave as it moves from one medium to another
11.
Explain why refraction occurs at the boundaries between mediums.
12.
List the types of electromagnetic radiation in order of ascending (increasing) frequency. And
label list to also indicated direction of increase of wavelength and energy.
13.
Give one example of how each of radio waves, microwaves, IR and visible light are used in
communications.
14.
Explain how to calculate the wavelength of a wave from a diagram of a wave.
15.
What is diffraction?
16.
Describe diffraction of a wave at an opening with a diagram.
17.
Describe how a wave diffracts as the size of an opening decreases (compare to the wavelength).
18.
How does the wavelength of radiation affect the physical size of the emitter or the receiver,
used in communications?
19.
Rewrite the wave equation to have wavelength as the subject; and again for frequency.
20.
Explain how diffraction limits the effectiveness of a) a telescope and b) an optical microscope.
P1d. Light and Lasers. [Due Mon 26th of March]
1.
Why do we need to use a code to send information by light?
2.
How does using light for communications affect the speed of communication.
3.
Describe how light can be used to send morse code
4.
What happens to light when it travels across a glass-air, water-air or perspex-air boundary?
5.
What is total internal reflection?
6.
When does TIR happen?
7.
Explain how optical fibers can transmit light and infrared radiation.
8.
What is the critical angle for total internal reflection.
9.
Explain how laser lights properties are different to light from other sources.
10.
Which property of laser light makes it useful for, a) surgery and dental treatment, b) cutting
materials in industry, c) weapon guidance d) laser light shows.
11.
Why is Morse code a digital signal?
12.
Describe on application of total internal reflection.
13.
Explain what coherent means – in terms of laser light.
14.
Explain how a laser is used in a CD player.
15.
How is information stored on a CD?
P1e. Cooking and communicating using waves. [Due Mon 23rd of April]
1)
How is the emission and absorption of infrared radiation affected by the following properties of
a surface? 1) Surface temperature b) Colour (black or white) and c) texture (dull or shiny)
2)
What is the main difference between infrared radiation and microwave radiation?
3)
Why are microwave ovens more energy efficient than traditional gas or wood ovens?
4)
How do microwaves cause heating of foods?
5)
List the main properties of microwaves that are important for cooking and protecting humans
during cooking.
6)
What are the differences in how microwaves and infrared radiations heat food?
7)
What type of electromagnetic radiation is used by mobile phones?
8)
What concerns are there about using mobile phones?
9)
How are these concerns different when thinking about children?
10)
Do scientists agree that mobile phones are safe?
11)
What factors limit the transmission of microwaves over long distances?
12)
How might the risks of using a mobile phone be different for people who live near mobile
phone transmitter masts compared to people who only use the mobile phone handsets?
13)
How might the risks of using a mobile phone be affected by a) using the phone more often, b)
using the phone for longer and c) using the phone in a poor reception area?
P1f. Data transmission. [Due 30th April}
1)
What is meant by; Data? A signal? Transmission?
2)
Describe two uses of IR radiation in the home for communications.
3)
Explain how infrared radiation can carry information to control electrical devices.
4)
How can the same infrared remote control be used for different devices or different functions on
the same device?
5)
What is a passive infra red sensor?
6)
How do thermal imaging cameras work?
7)
How are these last used?
8)
Explain what is meant by an analogue signal.
9)
Explain what is meant by a digital signal.
10)
List the main differences between analogue and digital signals.
11)
What are noise and attenuation, to a signal?
12)
Why is it easier to remove noise from a digital signal than an analogue signal without
corrupting the information.
13)
Why has the UK television service be switched from analogue to digital?
14)
What is multiplexing, in signal transmission?
15)
How do optical fibers help us to transmit information using light?
16)
What are the advantages of using optical fibers? Ie How do they allow more information to be
transmitted than copper wires.
P1g. Wireless signals [Due Mon 7th May]
1)
What do we mean by wireless communication? What carries the signals?
2)
What happens to radiation when it reaches the interface (or boundary) between two different
materials? And between two different regions of the atmosphere?
3)
What are the advantages of wireless technology?
4)
List three common uses for wireless technology?
5)
What is needed to send and receive wireless signals?
6)
Why do radio stations use different transmission frequencies?
7)
What does DAB stand for?
8)
List the advantages and disadvantages of DAB broadcasts?
9)
List the advantages and disadvantages of reflection and refraction of radiation for good signal
and reception?
10)
How does diffraction by transmission dishes affect signal strength?
11)
Explain the advantages and the disadvantages of the ionosphere to long distance
communications.
12)
Explain the role of satellites in long distance communications.
13)
How must the type of radiation be changed for use in satellite communications compared with
long distance terrestrial radio signals?
P1h, Stable Earth. [Due Mon 14th of May]
1)
2)
What is an earthquake?
What are the epicenter and the focus of an earthquake?
3)
Why are earthquakes dangerous?
4)
How are earthquakes caused?
5)
How are earthquakes detected by scientists?
6)
How are earthquakes recorded by scientists?
7)
What scale are the magnitude (amount of energy contained or amplitude of waves etc) of
earthquakes recorded on?
8)
What other geohazards are associated with earthquakes and state whether they can be caused by
earthquakes or can themselves cause earthquakes.
9)
What is a Tsunami and how are they caused?
10)
What are seismic waves?
11)
What are the two types of seismic wave called?
12)
Which type of seismic wave travels fastest?
13)
Which type of seismic wave only travels through solid materials?
14)
How do seismic waves provide evidence for the layered structure of the Earth?
15)
Describe the four layers of the Earth.
16)
What happens to a seismic wave when it reaches the interface between one layer and the next?
17)
In what ways can exposure to ultraviolet radiation affect human bodies and health?
18)
What does SPF sun protection factor mean?
19)
How much longer can a person remain exposed to ultraviolet light when wearing SPF 30
without burning than when not using sunscreens?
20)
How does a sunscreen (sunblock or sun tan lotion) protect our health?
21)
What natural protection does the human body have against damaging UV radiation?
22)
Explain the advantages and disadvantages of light skin vs dark skin in terms of exposure to
ultraviolet radiation.
23)
What is the ozone layer?
24)
What does the Ozone layer have to do with Global Warming and the greenhouse effect?
25)
How does the ozone layer protect life on earth?
26)
What happens to an ozone molecule when an ultraviolet ray hit it?
27)
What has happened to the ozone layer?
28)
What are CFC's?
29)
What have world governments done in response to the hole in the ozone layer?
30)
Explain how scientists increase confidence in their measurements or theories.