Winter 1P - 2022

Question 1

State the name of a material that would be suitable for use as a permanent magnet. (1)

Answer 1

.steel/ nickel/ cobalt

Question 2

State how a scientist should correct the count rate for background radiation. (1)

Answer 2

Subtract the background count rate

Question 3

Explain what is meant by the term half-life (2)

Answer 3

How long it takes half the radioactive nuclei to decay

Question 4

State a similarity of the Wi-Fi signals at 2.4GHz and 5.2 GHz. (Electromagnetic wave) (1)

Answer 4

Both are transverse (can travel in a vacuum)

Question 5

Explain the shape of the graph from A to C

(you should use ideas about forces to help your answer) (4)

Answer 5

. A➡️B object is accelerating, downward force is greater than upward force (at A)

. The faster the object moves the greater the air resistance (therefore resultant force decreases)

. Gradient/ acceleration decreases from A➡️B

. B➡️C graph levels off and object reaches terminal velocity

Question 6

Explain how the reading on a voltmeter changes when the temperature of the room decreases. (3)

Answer 6

. Reading in the voltmeter decreases
. As resistance of the thermistor increases current in the thermistor decreases

Question 7

State how the gravitational store of a rocket changes as the rocket burns fuel (1)

Answer 7

It increases

Question 8

Red light has a longer wavelength than violet light

. Deduce a possible relationship between the wavelength and the refractive index for colours of the visible spectrum (3)

Answer 8

. The longer the wavelength the lower the refractive index

. Red light refracts less than violet

. Red has a lower refractive index than violet

Question 9

Use ideas about thermal energy transfer to explain how the temperature of each metal bar changes as Funcube-1 spins (4)

Answer 9

. Bars increase in temperature when facing towards the sun/ decrease in temp when facing away from sun

. When facing sun black bar increases in temperature faster than white bar

. Because black is a better absorber of radiation than white

. So black reaches higher temperature than white

. When facing away from sun, black bar decreases in temperature faster than the white bar

. As black is a better emitter of radiation than white

. No convection or conduction takes place

. As there are no particles outside the aircraft

Question 10

Explain why the temperature of the air in a balloon decreases when the temperature of the air decreases (3)

Answer 10

Reduction in temperature reduces the kinetic energy of particles

So there are fewer collisions with the walls per unit time

Each collision with the wall is less forceful/ ‘hard’

Force (per unit area) on the container decreases

Question 11

Explain why the coil starts to rotate when there is a current in the coil (4)

Answer 11

. Current/ coil has a magnetic field

. There is an interaction between two fields

. This results in a force

. The forces on opposite sides of the coil are in opposite directions

Question 12

Which side of the coil moves vertically upwards

Answer 12

. YZ