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133 Cards in this Set

  • Front
  • Back

Microwaves and X-rays are both electromagnetic waves. What statement is correct for microwaves and X-rays in a vacuum?


Their speeds are... their frequencies are...:


A different, different`


B different, the same


C the same, different


D the same,the same


(1)

C) they travel in the same speed in a vacuum, have different frequencies

State one harmful effect of X-rays on living matter (1)

• Damages/ ionises/ mutates cells


• Damages/ ionises/ mutates DNA


• Damages/ ionises/ mutates tissue


• Damages/ ionises/ mutates organs


• Damages/ ionises/ mutates foetus


• Causes cancer/tumour

X-rays are ionising radiation.


State one other ionising radiation in the electromagnetic spectrum (1)

Gamma, UV/ Ultraviolet


(rays/waves/radiation)

State one use of an ionising radiation (1)

• UV:- sunbeds, sterilise, detect bank notes


• X-ray:- viewing internal organs/ broken bones, for airport security


• Gamma ray:- treat/ cure cancer, kill cells/bacteria

Describe a use of gamma radiation (2)

• sterilising food/ medical equipment detection/ • treatment of cancer imaging/ detect flaws in materials (1)


• some relevant detail about how it achieves the purpose (1)

Gamma rays can cause cancer. Gamma rays can also be used to treat cancer.


Explain how gamma rays can do both.(3)

•gammas change cell growth/ kill/ damage cells (1)


• (so can) cause uncontrolled growth/ mutate/ damage DNA (1)


• (but also can) be focused to(kill cancer cells) (1)


• without damaging other cellsT

State one way in which microwave radiation can be harmful to people (1)

• heating of body/ human/ blood


• heating of internal cells/ organs/ tissues


• heating/ boiling/ vibrating/ exciting water (in the body)

The microwaves used in ovens have a frequency of about 2450 MHz. Mobile phones emit microwaves with a frequency of about 2000 MHz.


Microwave ovens have shielding to protect people from the microwave radiation.


Suggest why the same shielding is not necessary for mobile phones (3)

• phones use lower frequencies/ energy/ wavelength/ RA (1)


• lower frequency does less/ no damage/ harm (2)


• phones emit less (intense) radiation (1)


• lower frequency/ energy means less (potential) danger/ RA (1)


• phones are less powerful (1)



The radiation that causes skin cancer is:


A ultraviolet radiation


B radio waves


C microwaves


D infrared radiation


(1)

A) ultraviolet radiation

Which of these ionising radiations is from a radioactive source and is also part of the electromagnetic spectrum?
A alpha particles


B beta particles


C gamma rays


D X-rays


(1)

C) gamma rays

Which of these is correct for all electromagnetic waves in a vacuum?


A they have the same frequency


B they have the same wavelength


C they are transverse waves


D they are longitudinal waves


(1)

C) they are transverse waves

Which parts of the electromagnetic spectrum are used for both communication and cooking?


A infrared and microwaves


B infrared and radio waves


C microwaves and radio waves


D radio waves and X-rays


(1)

A) infrared and microwaves

Fluorescent substances absorb ultraviolet and emit visible light. Visible light has a:


A faster speed than ultraviolet


B higher frequency than ultraviolet


C lower frequency than ultraviolet


D smaller wavelength than ultraviolet


(1)

C) lower frequency than ultraviolet

Different types of electromagnetic radiation have different uses. 
 Draw one straight line from each use to the correct type of radiation (3)

Different types of electromagnetic radiation have different uses.


Draw one straight line from each use to the correct type of radiation (3)

Herschel and Ritter carried out experiments that contributed to the discovery infrared and ultraviolet radiation.


Explain how the results of the experiments carried out by Herschel and Ritter led to these discoveries (6)

Results obtained:


• Herschel: temperature on thermometer


• Ritter: speed of darkening of silver chloride paper


Trend of results:


• Herschel: hotter towards red end


• Ritter: quicker towards blue/violet endExtension of experiment to get more results:


• Herschel: measure below red; found it even hotter


• Ritter: measure above blue/violet; paper darkenedquicker


Conclusion:


• Herschel: Must be radiation below red ( Infra Red)


• Ritter: Must be radiation above blue/violet ( UV)

X-rays from a star travel to a space telescope in orbit around the Earth.


Explain why visible light from the same star takes the same time to reach the telescope (2)

• (all e-m waves) have same speed (1)


• in {space/vacuum} (1)

An X-ray of wavelength 2.0 nm has a frequency of 1.5 1017 Hz.


1.0 nm = 1.0 10–9 m


Calculate the speed of the wave (2)

•substitution


i.e. (v =) 1.5 x 1017 x 2 x 10-9 (1)


•evaluation


i.e. (v =) 3 x 108 m/s (1)

Ultraviolet radiation and infrared radiation are emitted by the Sun and reach the surface of the Earth.


Describe a harmful effect of ultraviolet radiation (2)

• UV penetrates the skin / can damage normal cells/ cause cell/ tissue mutation/ ionise cells (1)


• can cause (skin) cancer/ sunburn/can cause premature ageing(1)




• UV penetrates the eye / can damage/mutate cells in the eye (1)


• can cause cataracts /damage to the retina (macular degeneration) (1)

Explain why ultraviolet radiation is likely to be more dangerous to humans than infrared radiation.(2)

•(ultraviolet/ it) has a higher frequency/ shorter wavelength (than infrared) (1)


• (therefore ultraviolet/ it) has higher (photon) energy (1)


• (ultraviolet/ it) penetrates further/ (ultraviolet /it)causes ionisation (1)

X-rays are:


A electromagnetic waves with very high frequency


B electromagnetic waves with very long wavelength


C electromagnetic waves which always have low energy


D ionising radiations emitted by radioactive sources

A) electromagnetic waves with very high frequency

Some users believed that sunglasses would protect their eyes from the X-rays.


Explain how effective this would be as a precaution.(2)

• {very little effect / not effective} {would not protect eyes}(1)


• {X-rays can easily penetrate sunglasses} {do not stop x-rays} (1)

A hair removal device was banned in 1940. Many people who had used it for a long time had become seriously ill.


State one of the effects this machine may have had on them.(1)

• cancer


•damage to cells


•damage to DNA


•damage to tissue


•damage to bones


•damage to skin


•damage to organs


•killing cells


•mutation


•mutating cells


•marks on skin


•sterilisation


•infertility


•re-arrangement of cell structure


•radiation poisoning

A hair removal device was advertised as ‘harmless’.


Suggest why people used this device for many years.(2)

•took a long time for effects to become apparent (1)


• it was new /scientific (1)


• risks not properlyunderstood (1)


• it removed hairsuccessfully (1)

There is a hair removal device which is currently available in some specialist clinics.It uses a low energy infrared laser beam. The makers say that this is much less dangerous than the X-ray device.


By considering the dangers associated with both devices, discuss whether the infrared laser device should be put on general sale to the public.(6)

A discussion to include some of the following facts:


• infrared frequency much lower than X-rays


• X-rays very penetrating


• X-rays potentially more dangerous to the operator


• infrared can cause skin burns


• laser is very concentrated


• specialised clinics are controlled environments


• safe operation depends on training


• our knowledge of EM radiation is still not complete


The discussion makes some of the following links:


• lower frequency of infrared makes it potentially less dangerousthan X-rays


• high penetration of X-rays makes it difficult provide adequateshielding


• the concentration of energy by the infrared laser makes itmore dangerous than otherwise


• controlled environment of a clinic provides better safety andmore thorough training


• difficulty of ensuring proper maintenance /correct dosage ifused domestically


• lack of knowledge could mean there are long term effects stillnot known


The discussion makes some of the following conclusions:


• easier shielding of infrared compared to X-rays means there isless risk to operators and /or patient


• difficulty of ensuring proper control means it is not suitable fordomestic use


• lack of full understanding of long term effects means it isbetter to err on side of caution

Explain why step-down transformers are used in the transmission of electricity in the National Grid (2)

• (so that they) decrease (high) voltages (1)


• high voltages used for efficiency/ energy saving (1)


• (step-down transformers) are used {near/ for} {homes/ factories/ appliances} (1)


• (so that it is) safer (1)


• less risk of electrocution (1)


• high voltages are dangerous (1)

All electromagnetic waves are:


A longitudinal and have the same amplitude in a vacuum


B longitudinal and have the same speed in a vacuum


C transverse and have the same amplitude in a vacuum


D transverse and have the same speed in a vacuum


(1)

D) transverse and have the same speed in a vacuum

All electromagnetic waves have both uses and dangers.


Their potential danger increases when:


A frequency decreases and wavelength decreases


B frequency increases and wavelength decreases


C frequency decreases and wavelength increases


D frequency increases and wavelength increases


(1)

B) frequency increases and wavelength decreases

Some microwaves have a frequency of
1.5 × 1010 Hz.


They travel at a speed of 3.0 × 108 m/s.


Calculate their wavelength.(3)

• substitution: (1)


3.0 × 108 =1.5 × 1010 × λ


• transposition: (1)


λ = c/f or(λ =)3.0 × 108 1.5 × 1010


• evaluation: (1)


0.02 (m) or 2 × 10-2 (m)

Infrared is used in an electric toaster. Infrared is also used by a television remote control.


Explain why using a television remote control does not burn anyone.(2)

• wavelength / frequency (1)


• are different (1)


OR


• toaster on for longer (1)


• (so) much more energy (1)




• wavelength for toaster different from wavelength for remote (2)


• power/ intensity of toaster greater than for remote for (2)

A transformer has 2400 turns on the primary coil and 100 turns on the secondary coil.


Calculate the secondary voltage if the primary voltage is 12 V.(3)

• Transposition (1)


Vs = Vp x Ns/Np


• Substitution (1)


(Vs =) 12 x 100 2400


• Evaluation (1)


0.5 (V)

Eric looks at the cost of installing the turbine. State how he should work out the payback time (1)

Divide the installation cost by the annual saving (to find the time in years)(1)

The chicks need to be kept warm at all times. Eric uses halogen lamps to provide heat and light for most of the day.


Eric thinks about changing his halogen lamps for energy saving lamps.


Suggest why this might not actually be a benefit.(2)

• (energy saving lamps) would not transfer so much thermal energy(1)


• he may have to use additional heating / lights (which would cost money to run/ purchase) (1)

There are several large-scale energy resources which are suitable alternatives to fossil fuels in some situations.


Two of these alternatives are hydro-electric power and solar power.


Compare hydro-electric power with solar power as energy resources for the large-scale generation of electricity.(6)

• Both HEP and Solar power are renewable


• Both HEP and Solar power would save fossil fuels


• HEP only possible in some locations


• HEP requires reservoirs and damming of rivers


• This can damage environment /takes a lot of land out ofuse


• Energy from solar power installation is currently muchless than energy from fossil fuel powered station


• Solar power only suitable in certain locations


• Solar power reliability dependent on constant sunshine


• Neither of them cause atmospheric pollution

Draw one straight line from each train part to its useful energy transfer (3)

Draw one straight line from each train part to its useful energy transfer (3)

State one example of a non-useful energy transfer in the motor (1)

State one example of a non-useful energy transfer in the motor (1)

(transfer of energy to) thermal / heat / sound (1)

The electric motors which drive the wheels are painted black.


Suggest why the motors are painted black (1)

• black is a good thermal radiator / (good) emitter (1)


• (helps to) prevent motors overheating (1)


• (helps to) remove wasted energy/ heat (from the motor) (1)

A small notebook computer has a power rating of 40 W. The computer is connected to the mains supply through a step-down transformer. The mains supply is a.c.


How much energy is supplied to the computer each second?


A 0.025 J


B 4.0 J


C 40 J


D 240 J


(1)

C) 40 J

The step-down transformer has: 2400 turns on the primary coil, 200 turns on the secondary coil and a primary voltage of 230 V.


Calculate the voltage output of the secondary coil (3)

•substitution (1)


2400/200 = 230/ Vs


•transposition (1)


(Vs =) 230 x 200/2400


•Evaluation (1)


(Vs =) 19 (V)

Explain how transformers are used to improve the efficiency of powertransmission in the National Grid (3)

•step-up transformer(s) (1)


• increase voltages (1)


• (this) reduces the current(1)


• (which) reduces the {heat /thermal} {energy /power} losses (1)

Explain why flying a kite near power lines could be a danger to the personflying the kite (2)

• kite / string touching thepower line (1)


• movement of charge /current (1)


• (electricity) to earth /through the kite-flyer (1)


• giving (the kite-flyer) anelectric shock/ electrocution (1)

A 100 W filament lamp is 15% efficient.


Explain the meaning of the term 15% efficient.(2)

•15 % of power /energy (1)


• is transferred usefully (1)


• 85% of power / energy (1)


• is wasted (1)

Many people choose to buy expensive low-energy lamps instead of cheaperfilament lamps. Give two reasons for this.(2)

• Energy, e.g. (low-energylamps) are more efficient /waste less energy / produceless heat (1)


• Economy, e.g. (low-energylamps) use less electricalenergy /cost less to run /have a lower power (rating) (1); idea of Payback, e.g. (low-energylamps) are (more) cost effective(over time) (1)


• Environment, e.g. using(low-energy lamps) reducesCO2 emissions / saves fossilfuel (1)


• Practical, e.g. (low-energylamps) last longer / needreplacing less often / (canbe) easier to obtain (1); filament lamps (have been)banned (in some countries) (1)

When a filament lamp is in use, the temperature of the wire filament remains at 2500 °C.


Explain why this temperature remains constant.(3)

• energy gain is from powersupply (1)


• energy loss is byradiation (1)


• the loss and the gain areequal /at the same rate / in equilibrium (1)

‘All the energy supplied to the motor eventually ends up as thermal energy in the surroundings.’ This statement best describes the idea of:


A renewable energy


B energy efficiency


C sustainable energy sources


D conservation of energy


(1)

D) conservation of energy

The current in a motor is 0.5 A.


The potential difference (voltage) across the motor is 6 V.


Calculate the input power to the motor. State the unit (3)

•substitution (1)


0.5 × 6.0


•evaluation (1)


3 / 0.003


•unit (1)


W / watts / kW / kilowatts

State the difference between the currents which makes one alternating and the other direct (1)

•alternating current can take positiveand negative values(1)


•a.c. above and below zero /the linea.c. goes one way and then theother (1)


•a.c. above and below zero /the linea.c. goes one way and then theother (1)

A transformer is 100% efficient. It has 200 turns on the primary coil and 3000 turns on the secondary coil. The input voltage is 55 V.


Show that the output voltage is about 800 V (3)

•substitution: (1)


55/V = 200/3000


•transposition: (1)


V = 3000/200 x 55


•evaluation / comment: (1)


825(V) / which is about 800 (V)

Calculate the current in the secondary coil when the current in the primarycoil is 0.50 A (2)

• power input = power output(1)
•power input = 55 x 0.5 (W) (1)


•power input = 27.5 (W) (1)


• I = 0.033 (A)/ I = 0.034 (A) (1)

The diagram shows how electricity produced at a power station is transmitted to
distant houses.
Transformers R and S are not 100% efficient.
By using transformers, energy losses in the transmission lines are reduced. 
Explain how this reduction...

The diagram shows how electricity produced at a power station is transmitted todistant houses.


Transformers R and S are not 100% efficient.


By using transformers, energy losses in the transmission lines are reduced.


Explain how this reduction is achieved, even though some energy is wasted in thetransformers themselves (6)

Basic ideas:


• transmission lines have resistance


• the current warms the transmission wires


• energy is wasted as heat


• transformers change voltage and/or current


• R increase the voltage / RA for S


• R decrease the current / RA for S


Linked ideas:


• the long transmission lines have high resistance


• power depends on both current and voltage


• power = current × voltage (P = I × V)


• at high voltage, the same power needs less current


• correct mention of turns ratio related to voltage change


• a smaller current in a wire produces less heat


• high voltage transmission saves more energy than is lost in thetransformers

Which statement is true?


When held stationary:


A a spring has zero elastic potential energy


B a weight has equal amounts of elastic potential and kinetic energy


C a weight has more kinetic energy than gravitational potential energy


D a spring has more elastic potential energy than the weight has kinetic energy


(1)

D) the spring has more elasticpotential energy than theweight has kinetic energy

A spring is stretched and is then released.


Describe the energy changes that take place until the spring stops vibrating (3)

• Elastic potential energy / EPE (in stretched spring) (1)


• (EPE is) transferred to KE (initially) (1)


• change from KE to GPE or vice versa(1)


• (correct idea of) energy changes continuing


• {total mechanical energy/kinetic +potential energy}decreases (continuously) (1)


• (Eventually all is transferred to) {thermal/heat} (energy)(1)

Explain how shock absorbers can provide electrical energy (2)

•(bump produces) relativemotion / coil moves round magnet/magnetmoves {into/out of} coil / coil{cuts / moves across} magneticfield(1)


•(motion between magnetand coil) {induces /generates} voltage (1)



The diagram shows the bumps on the surface of two roads, L and M.
 Explain why the device will transfer more energy on road L than on road M for
a motorcycle travelling at the same speed (3)

The diagram shows the bumps on the surface of two roads, L and M. Explain why the device will transfer more energy on road L than on road M fora motorcycle travelling at the same speed (3)

•{more/frequent} bumps (idea of shorter time /increased frequency) / {more/frequent} bumps (1)


•idea of up and down for bump(coil / magnets) move up anddown {faster / more often} (1)


•(bigger bumps produce)bigger amplitude / movemore up and down (idea of bigger size) (1)


•(so) {induced voltage/ voltage generated} islarger (1)

The solar heating panels are painted black because:


A black is a good absorber of heat


B black is a good conductor of heat


C black is a good radiator of heat


D black is a good reflector of heat


(1)


A) black is a good absorber of heat

On one sunny day no hot water is used in the house. The water in the panels reaches a constant temperature even though thewater is still absorbing energy from the Sun.


Explain why the temperature of the water in the panels becomes constant.(3)

•{energy / heat / radiation}is lost (1)


• (heat lost) = heat gained /absorbed (1)


• rate (of heat loss) = rate(of heat gained) (1)


• description of dynamic equilibrium (3)

Which energy transfer takes place in a solar cell? A chemical to electrical


B electrical to light


C electrical to chemical


D light to electrical


(1)

D) light to electrical

A large solar farm has 21 700 solar panels and generates 5.0 MW of power.


1.0 MW = 1.0 106 W


Calculate the average power each panel produces (2)

•substitution (1)


5 000 000 / 21 700


•evaluation (1)


230 W

The solar farm receives 25 MW of power from the Sun to generate 5 MW ofelectrical power.


Calculate the efficiency of the solar farm (2)

•substitution (1)


5 x 100 / 25


•evaluation (1)


20(%)

State one disadvantage of using the wind to generate electrical power (1)

• unreliability (1)


e.g. wind does not alwaysblow / wind speed may betoo high/too low


• pollution (1)


e.g. noise from windturbines / wind turbinesspoil the view

A wind farm generates 322 MW of electrical power.


The wind farm is connected to a transmission line at a potential differenceof 132 kV.


Calculate the current from the wind farm (3)

•transposition (1)


current = power ÷ voltage


•substitution (1)


322 000 000 ÷ 132 000


•evaluation (1)


2440 (A)

The wind farm produces 322 MW of power. The wind farm is to be extended by adding 75 improved turbines.


The extended wind farm will then produce a total of 539 MW.


Calculate the power produced by each improved turbine (2)

• calculation to find additionalpower generated


e.g. 539 – 322 = 217 (MW) (1)


• 2.9 (MW) (1)

There is a plan to replace the existing transmission line from the wind farm withone at the higher potential difference of 400 kV.


The new transmission line will cross more than 200 km of mountains.


The cables will hang 50 m above the ground from 600 new, taller pylons.


Eventually, about 1000 of the old, shorter pylons will be removed.


Discuss the advantages and disadvantages of this plan.(6)

Social factors / Economic factors:-


• people may not like it / pressure groups


• cost arguments


Environmental factors:-


• spoiled view / risk of birdstrike


• space for extra infrastructure; eg. access roads / substations


Associated hazards:-


• danger from higher voltage


• dangers from construction work in mountainous area


• danger to maintenance crew from working at greater height


Energy efficiency arguments:-


• higher voltage leads to lower current


• lower current means reduced heat losses


• higher voltage means / lower current / can transmit energyfurther


• reduced heat loss means improved efficiency


Logical use of data:-


• taller pylons can be seen from further away


• net reduction in number of pylons / need to remove old ones


• stronger materials needed for pylons / cables


• need for new transformers


Appropriate calculations:-


• 1000 - 600 = 400 fewer pylons (approx)


• current reduced by a factor of 132/400 (0.33)

Students read the statement: ‘All the energy supplied to the motor eventuallyends up as thermal energy in the surroundings.’


This statement best describes the idea of:


A renewable energy


B energy efficiency


C sustainable energy sources


D conservation of energy


(1)

D) conservation of energy

Students use an electric motor to lift a weight.


The current in the motor is 0.5 A.


The potential difference (voltage) across the motor is 6 V.


Calculate the input power to the motor. State the unit (3)

•substitution (1)


0.5 × 6.0


•evaluation (1)


3


•unit (1)


W / watts

How much energy is wasted?
(1)

How much energy is wasted?(1)

150 (J)



Calculate the efficiency of the motor.
(2)

Calculate the efficiency of the motor.(2)

•substitution (1)


50 ÷ 200 (x 100%)


•evaluation (1)


25 (%)

The case of a motor is painted black.


Give a scientific reason why the case of the motor is painted black (1)

•(black) is a good (thermal)emitter / radiator


•to keep the motor cool

The hosepipe is painted black because blackened surfaces are:


A good emitters of radiation


B poor emitters of radiation


C good absorbers of radiation


D poor absorbers of radiation


(1)

C) good absorbers of radiation

At first, the temperature of the water in the pipe increases. After a while, the temperature becomes constant.


Suggest two changes to the box which would increase the constanttemperature reached (2)

• cover box with transparentmaterial (1); e.g. glass / transparent box


• use of reflector; e.g. mirror / foil (1)


• method to increase energysupplied; e.g. {angle to sun} / {warmerplace}/lens (1)


• method to reduce energy loss; e.g. use insulating box / wooden box /lagging (1)


• paint (box) black/dull/matt(1)

Explain why the water reaches a constant temperature (3)

• pipe / water absorbs heat (1)


• pipe radiates heat (1)


• radiation (rate) increaseswith temperature (1)


• (at constant temperature)absorption rate = radiationrate (1)



Calculate the power absorbed by the heater (2)

Calculate the power absorbed by the heater (2)

•4000 (1)


•(4000)/200 (1)


• 20 W

State the two sound frequency ranges that human beings cannot hear (2)

• below 20 Hz (1)


•above {20 000 Hz / 20 kHz}(1)


• infrasound (1)


• ultrasound (1)

Which of the following is correct for a P-wave?


A It is a transverse wave travelling faster than an S-wave.


B It is a transverse wave travelling slower than an S-wave.


C It is a longitudinal wave travelling faster than an S-wave.


D It is a longitudinal wave travelling slower than an S-wave.


(1)

C) it is a longitudinal wavetravellingfaster than an S wave

Explain why the path of the P-wave is not a straight line (2)

Explain why the path of the P-wave is not a straight line (2)

•refraction /changing speed(1)


• (due to) changing{material/ medium/ rocktype/ density} (1)

Explain why there are regions on the Earth’s surface where S-waves from thecollision at X cannot be detected (3)

•(S / transverse waves)they cannot travel throughliquid / they can only travel through solids (1)


•Earth’s core is (at leastpart) {liquid/molten} (1)• (so) (S waves) theycannot travel through core(to other side of Earth) (1)


• they cannot be detected on oppositeside of the Earth to (collision site/ earthquake)

Describe how a meteor colliding with the Earth could set off an earthquake (2)

•{kineticenergy/force/ momentum}of meteor might cause theearthquake / meteors have large amounts of KE (1)


•(earthquakes happenwhere) plates slide{past/over/under/awayfrom/against} each other(1)


•(plates move) suddenly / jerk / jolt


•vibrations passing through theEarthcondone earthquake waves


•(meteor collision) startsseismic waves /P/S (1)


•{kinetic energy/force/momentum} of meteor cancause the plates to slide pasteach other (2)

The plates are being steadily pushed in opposite directions by:
A convection currents in the mantle
B reflection of waves from the Earth’s core
C tsunami waves in the ocean
D volcanic eruptions on the surface 
                      ...

The plates are being steadily pushed in opposite directions by:


A convection currents in the mantle


B reflection of waves from the Earth’s core


C tsunami waves in the ocean


D volcanic eruptions on the surface


(1)

A) Convection currents in the mantle

An earthquake occurs.
 Its epicentre is at the place marked E on the diagram.
 Describe what happens at the plate boundary to cause this earthquake (2)

An earthquake occurs. Its epicentre is at the place marked E on the diagram. Describe what happens at the plate boundary to cause this earthquake (2)

•plates move / slip / separate(relative to each other) (1)


•sudden (release of energy) (1)

S waves are one type of seismic wave. They travel at 0.65 km/s. There is a seismometer 80 km away from point E.


Show that it takes about 2 minutes for the S waves from the earthquake toreach the seismometer (2)

•substitution (1)


0.65 = 80 / t


•transposition (1)


t = 80 / 0.65(123 seconds)

P waves are a type of seismic wave.


They travel about 10 times more quickly than S waves.


Describe how scientists can use seismometer records of P and S waves tolocate the epicentre (3)

•detection of arrival of P and Swaves (1)


•measurement of difference inarrival times (1)


•calculation of distance (fromepicentre to station) (1)


•triangulation/using three /several stations (1)

Seismic waves have a frequency of about 15 Hz. P waves have a much smaller amplitude than S waves.


Some people claim that animals can detect an earthquake before people areaware of it.


Suggest an explanation for this (2)

•Infrasound (1)


•some animals can hear wavesbelow human frequency range /20 Hz (1)


•they could hear P waves arrivingbefore the (stronger) S wavesarrive (1)

Ultrasound is used for:


A cooking


B communication between animals


C communication with satellites


D detecting forged bank notes


(1)

B) communication between animals

Explain why ultrasound rather than X-rays are used for foetal scanning (2)

•{X- rays are / ultrasoundis not} dangerous (1)


• X-rays are ionising /ultrasound is not ionising (1)


• (because X-rays) can{damage / harm} {tissue/ DNA} ORmutate cellsORreverse argument forultrasound (1)


•X-rays cause cancer (1)

An ultrasound wave vibrates 30 000 times a second.


State the frequency of the wave (1)

30 000 Hz / hertz

Describe the motion of particles in a material when this ultrasound wavepasses through (2)

•they /particles {vibrate / oscillate} (1)


•(move) in the {same direction as/ parallel to the direction } thewave travels (1)

Explain how sonar is used by deep sea fishermen to detect the depth of a shoal offish below the surface of the sea (6)

• sonar is ultrasound


• sonar travels through water at the speed of sound (1500 m/s)


• ultrasound signal generated in the ship


• signal emitted from the bottom of the ship


• signal travels down through the water


• strikes shoal of fish


• signal reflected by fish


• reflected signal detected on the ship


• time between emission and detection measured


• either time halved and depth of fish calculated /ordistance wave travelled calculated and halved to givedepth of fish


• calculation done using x = v x t


• comparison of depths of fish and of seabed

Sound travels through the air as longitudinal waves.


Describe how the air particles move when a sound wave passes (2)

• (Particles) vibrate/oscillate(1)


• (vibration) parallel todirection of wave /propagation (1)

Which of the following statements is the reason that people cannot hear infrasound?


A the amplitude of infrasound is too big


B the frequency of infrasound is too low


C the speed of infrasound is too fast


D the wavelength of infrasound is too short


(1)

B) the frequency of infasound is too low

Two elephants use infrasound waves for long distance communication. The distance between these two elephants is 2500 m.


Elephant A emits an infrasound call. When elephant B hears the infrasound, it calls back. Elephant A hears the answering call from elephant B.


The speed of infrasound is 340 m/s.


Show that the minimum time for elephant A to call and hear an answer fromelephant B is about 15 s (3)

•transposition (1)


t = distance ÷ speed


•substitution (1)


(2 x )2500 ÷ 340


•evaluation (1)


14.7 (s), which rounds up to 15 (s)

An elephant’s infrasound call has a range of 4000 m. Each infrasound call lasts between 2 s and 10 s. Each elephant usually waits about 30 s before it calls again.


Suggest a reason why elephants wait 30 s before calling again (1)

• idea of a conversation (1)


• (4000 m is) a longerdistance taking a longertime (to reach otherelephant) (1)


• time needed for waves totravel is about 24 s (1)


• time gap between calls(sufficient) for elephant tohear a reply (1)


• call lasts long enough to beidentified by other elephants (1)

Describe a use of infrasound that does not involve animals (2)

•detecting/ locating/monitoring (infrasound) (1)• volcanic eruptions /underground explosions /earthquakes /nuclearexplosions / meteor strikes(1)

Which row of the table is correct for these waves?

Which row of the table is correct for these waves?

D

The chart shows how the speed of P-waves varies with the depth in the Earth’s
mantle.
State what happens to a P-wave when it crosses from the mantle into the core (1)

The chart shows how the speed of P-waves varies with the depth in the Earth’smantle.


State what happens to a P-wave when it crosses from the mantle into the core (1)

(sudden) decrease in speed / refraction / change in direction (1)

Describe how the speed of a P-wave changes between a depth of 1000 kmand 2500 km (2)

•the (speed) increases (1)


• as depth increases (1)


• linearly (1)


• from 11.8 to 14 (km/s) (1)


• by 2.2

The average speed of a P-wave in the mantle is 12 km/s. A P-wave travels vertically down from the surface and reflects from thecore–mantle boundary back to the surface.


It travels a total distance of 5800 km.


Calculate the total time of travel for the wave (3)

•substitution (1)


12 = 5800 ÷ t


•transposition (1)


t = 5800 ÷ 12


•evaluation (1)


480 (s) / 8 minutes

Explain what the results show about predicting earthquakes (2)

Explain what the results show about predicting earthquakes (2)

• impossible / difficult to predictearthquakes (1)


• (because) no pattern to{results/forces} (1)


OR


• (because) not able topredict force needed tomake block start sliding (1)


OR


• the movement of (tectonic)plates is similar to themovement of the block(over the rough surface) (1)

State the name of the effect shown in this diagram (1)

State the name of the effect shown in this diagram (1)

Refraction

When the waves go from deep water to shallow water, the:


A frequency decreases


B wavelength decreases


C frequency increases


D wavelength increases


(1)



B) wavelength decreases

Explain another change which can be seen from the diagram when the waves
go from deep water to shallow water (2)

Explain another change which can be seen from the diagram when the wavesgo from deep water to shallow water (2)

• change in direction (1)


• towards the normal (1)


• (resulting from ) decreasein speed (1)


• (because) the left handpart of the wave front {hitsthe boundary first / slowsdown first} (1)

The velocity of the waves in deep water is 25 m/s. The wavelength is 120 m.


Calculate the frequency of the waves (3)

•substitution (1)


25 = 120 x f


•transposition (1)


f = 25/120


•evaluation (1)


0.21 (Hz)

Explain the difference between transverse and longitudinal waves by referring to
sound from the bell and the light from the lamp (3)

Explain the difference between transverse and longitudinal waves by referring tosound from the bell and the light from the lamp (3)

• light waves are transversewaves / sound waves arelongitudinal (1)


• in transverse wavesoscillations are at rightangle to the direction oftravel (1)


• in longitudinal wavesoscillations are parallel tothe direction of travel (1)

Which row of the table is correct for both infrasound radiation and infrared
radiation? (1)

Which row of the table is correct for both infrasound radiation and infraredradiation? (1)

C

State the amplitude of this wave (1)

State the amplitude of this wave (1)

5 (cm)

Describe how infrasound differs from ultrasound (2)

• A difference in f or λ(however described) (1)


This difference correctly qualified byone of:


• Relationship to each other(1)


• Relationship to audible sound(1)


• Frequency or wavelengthdata (1)



Explain how this model of corks on water could be used to demonstrate what
causes the Earth’s plates to move.
 You may add to the diagram to help with your answer (3)

Explain how this model of corks on water could be used to demonstrate whatcauses the Earth’s plates to move. You may add to the diagram to help with your answer (3)

•corks as plates / water as mantle / corks as crust /water as {magma / lava}(1)


• water heated (underneath)(1)


• convection currentsmentioned(1)

A student suggested that the time between the arrival of the P-wave and the
S-wave was proportional to the distance of the station from the earthquake.
 Use the charts to evaluate whether this is correct or not (3)

A student suggested that the time between the arrival of the P-wave and theS-wave was proportional to the distance of the station from the earthquake. Use the charts to evaluate whether this is correct or not (3)

• (a)statement about eitherdistance travelled or arrivaltimes of any two waves (1)


• (b)statement comparing anypair of S-P times (1)


• correct comparison between(a) and (b) leading to aconclusion (1)

Explain the purpose of the eyepiece in a telescope.(2)

•magnify (1)


•the (real) image fromobjective (lens) (1)


OR


• to provide greater detail / clearer image (1)

Galileo drew pictures of his observations of Jupiter. Nowadays we can take photographs.


Suggest how photographs would have helped Galileo (1)

•made recording results {easier/quicker} (1)


•results more convincing toother people (1)


•photograph is to scale (1)

The telescope collects light reflected from Jupiter. The light has a frequency of 4.30 × 1014 Hz and a speed of 3.00 × 108 m/s.


Calculate the wavelength of the light.(3)

•Substitution (1)


3.0 x 108 = 4.3 x 1014 x λ


•Transposition (1)


(λ=) 3.0 x 108 4.3 x 1014


•Evaluation (1)


6.98 x 10-7 (m)

Galileo’s observations of the moons of Jupiter disproved the geocentric model. However, these observations were not enough to prove the heliocentric model ofthe Solar System.


Explain why Galileo’s observations disproved one model but were not enough toprove the other model.(6)

• Description of models: geocentric and heliocentric


•The geocentric model saideverything orbited the Earth while the heliocentric was foreverything orbiting the Sun.


•Galileo’s observations that Jupiter hadmoons orbiting around it showed that the geocentric model waswrong but not that Jupiter or anything else went around the Sun.

Galileo was one of the first scientists to use a telescope to study Venus.
Which of these diagrams best shows how light waves enable us to see Venus? (1)

Galileo was one of the first scientists to use a telescope to study Venus.


Which of these diagrams best shows how light waves enable us to see Venus? (1)

D

Use words from the box to complete the sentences.
Galileo also used his telescope to observe the ... of Jupiter.
His observations provided evidence to support the ... model
of the Solar System.  

Use words from the box to complete the sentences.


Galileo also used his telescope to observe the ... of Jupiter.


His observations provided evidence to support the ... modelof the Solar System.

•moons (1)


•heliocentric (1)

Describe how a reflecting telescope is different from the simple telescopewhich Galileo used (2)

•Reflecting telescope hasmirror(s) (1)


•Galilean telescope has onlylenses (1)


•Reflecting telescope can gathermore light / can have a largerobjective (1)


•Image viewed from the side ofreflecting telescope (1)


•Image viewed from end of Galilean telescope (1)



State the amplitude and wavelength of the wave (2)

State the amplitude and wavelength of the wave (2)

•5 (cm) (1)


•8 (cm) (1)

20 waves are sent out in 4 seconds. The frequency of the wave is:


A 0.2 Hz


B 5 Hz


C 20 Hz


D 80 Hz


(1)

B) 5 Hz

At which point is the ray of light shown likely to leave the glass block?


A
B
C
D  

At which point is the ray of light shown likely to leave the glass block?


A


B


C


D

B

The ray of light changes direction when it enters the glass block because there
is a change of:
A amplitude
B frequency
C speed
D energy   

The ray of light changes direction when it enters the glass block because there is a change of:


A amplitude


B frequency


C speed


D energy

C

A student uses a lens to form a clear image of a house. The image is formed on a piece of paper. The house is a long way away.


Describe how the student should find the focal length of the lens (2)

• measuring the {distance /space} (1)


• between lens and {paper /image} (1)

Galileo used a telescope to observe Jupiter. His observations provided evidence to support the idea that the Earth is not the centre of the Universe.


Explain how Galileo’s observations supported this idea (2)

• moon(s) (1)


• (appear to) orbit Jupiter(not Earth) (1)


• (therefore) not everything orbits the Earth / the geocentric model is wrong (1)

The information sheet given with a simple telescope states:


•

the magnification is 40 times (40)
  the focal
•

length of the objective is 110 cm. 
Calculate the focal length of the eyepiece (3)

The information sheet given with a simple telescope states:


•the magnification is 40 times (40) the focal


•length of the objective is 110 cm.


Calculate the focal length of the eyepiece (3)

•rearrangement (1)


i.e. fe = fo / M


•substitution (1)


i.e. (fe =) 110 / 40


•evaluation (1)


i.e. (fe =) 2.8(cm)

The type of lens used as the objective lens is:


A concave


B converging


C diverging


D reflecting


(1)

B) converging

The image produced by the objective lens is:


A the right way up and smaller


B the right way up and bigger


C upside down and smaller


D upside down and bigger


(1)

C) upside down and smaller

Describe how the position of this image can be shown by using this apparatus (2)

Describe how the position of this image can be shown by using this apparatus (2)

• a paper / screen (betweenthe objective and theeyepiece) (1)


• move screen / lens (to andfro) (1)


• to obtain an image which isin focus / clear / sharp (1)

State the purpose of the eyepiece (1)

to magnify the image / increase the image size (producedby the objective) (1)

The telescope is used to look at the planet Venus. Assume that the distance from Venus to the Earth is 39 000 000 km.


The speed of light is 300 000 000 m/s.


Calculate the time it takes for light to travel from Venus to the Earth (3)

•transposition (1)


t = x/v


•substitution (1)


t = 39 000 000 000/300 000 000


•evaluation (1)


130 (s)

Which of these best describes what is transferred by the water wave?


A energy only


B water only


C both water and energy


D neither water nor energy


(1)

A) energy only

The wavelength of the wave is 0.8 m.
Calculate the distance between the floats (2)

The wavelength of the wave is 0.8 m.


Calculate the distance between the floats (2)

•(number of waves =) 7 (1)


•(distance between floats =) 7 × 0.8 (1)

A man on the shore observes the wave.


Suggest one piece of information the man could gain about the boat byobserving the wave that made it (1)

• size (1)


• mass (1)


• speed (1)


• direction of travel (1)

The frequency of the wave is 0.4 Hz.


How many complete wavelengths pass each float in 20 s?


A 0.02


B 0.8


C 8


D 50


(1)

C) 8

A star of much greater mass than the Sun will eventually become:


A a black hole


B a protostar


C a red dwarf


D a white dwarf


(1)



A) a black hole

Describe how the Sun reached its main sequence stage (3)

•in a nebula (1)


•(particles) attracted / cometogether by (force of)gravity (1)


•pe/ke transferred tothermal/heat energy (gasbegins to glow and formsprotostar) (1)


•until {hot / pressure /dense} enough to startnuclear reaction /fusion (1)

Scientists can estimate the age of a star.


They want to find the age of theoldest star.


Suggest why knowing the age of the oldest star is not enough to tell scientiststhe age of the Universe (2)

• the oldest star had not yetappeared when the {Big Banghappened / universestarted} (1)


•the Universe is older thanthe oldest star


• star takes time to form (1)


•can’t be certain of this time(1)

Edwin Hubble discovered that the Universe was expanding. He did this by using observations of red-shift. Explain what red-shift is and how it provides evidence that the Universe isexpanding (6)

•light shifted to red end of spectrum


•light waves are stretched so wavelength increases


•reference to black or spectral lines moving to ‘red end’(of absorption spectrum)


• frequency of wave from a moving source changes


• decrease in frequency means source moving away


• increase in frequency means source moving towardsus


• red shift shows galaxies are moving away from us


• greater red shift indicates galaxy moving away faster


• further away galaxies give greater red shift


• (nearly) all galaxies show red-shift


•red shift shows decrease in frequency


• blue shift shows increase in frequency


• therefore galaxies are moving apart


• [mention of Doppler effect]


• [outline of Doppler effect]