2019

Question 1

Explain the possible dangers caused by a vehicle having a large deceleration when it is braking

Answer 1

brakes overheating
causing a skid

Question 2

Explain why the iron rods move apart when the switch is closed

Answer 2

the rods become induced magnets
with the same polarity at each two

Question 3

Explain how the data in Figure 9 supports the suggestion that the universe began from a very small region

Answer 3

The furthest galaxies are moving the fastest
The universe is expanding from a small region

Question 4

What do the new observations suggest is happening to the universe?

Answer 4

Expanding at an ever greater rate
Expanding faster

Question 5

Give one reason why peer review is an important process

Answer 5

Detects false claims
detects bias
detects inaccurate data

Question 6

A galaxy is moving towards earth- how would the wavelength and frequency change when viewed from earth

Answer 6

Wavelength seems to decrease
Frequency seems to increase

Question 7

Inertia definition

Answer 7

The tendency of an object to continue in its state of rest or motion

Question 8

Explain how the properties of X rays make them suitable for the medical imaging of bones

Answer 8

Pass through soft tissue
Absorbed by bone and do not pass through

Question 9

The four temperature values cannot be used to show that the infrared detector gives precise readings. Why?

Answer 9

Measurements have not been repeated to show that they cluster closely

Question 10

Explain how using an infrared detector with a resoluation of 1 C would have affected the students conclusion

Answer 10

student could not conclude that black surfaces always emit more infrared than a white surface
as the reading for the matt white and shiny black would be 66 C

Question 11

Explain the changing motion of the skydiver in terms of forces acting on the skydiver

Answer 11

Initially air resistance is less than weight so the skydiver accelerates
acceleration causes the air resistance to increase
resultant force decreases to 0 and air resistance = weight
skydiver falls at terminal velocity

Question 12

Jumping from 40000 meters allows the skydiver to reach a much higher speed than 300m . Why?

Answer 12

The higher the altitude the less dense the air
So the air resistance on the skydiver was less
so the skydiver was able to accelerate for longer before reaching terminal velocity

Question 13

Function of a microphone?

Answer 13

To convert the pressure variations in sound waves to variations in potential difference/current

Question 14

Explain how a moving coil microphone works

Answer 14

sound waves cause the diaphragm to vibrate
the diaphragm causes the coil wire to vibrate
the coil cuts magnetic field lines
a pd is induced