Extra Extra paper 1

Question 1

State what happens to the kinetic energy when braking.

Answer 1

Heating of surroundings, thermal energy from brake pad/wheels.

Question 2

Which colour of visible light has the longest wavelength?

Answer 2

Red.

Question 3

Why may an infrared remote control not switch on the television from behind an armchair but a radio wave remote control always will?

Answer 3

Infrared blocked/absorbed by chair. Different wavelength and frequency. Infrared may need to be in line of sight.

Question 4

How could a student use a semi-circular glass block to determine the critical angle?

Answer 4

Fire ray of light at curved face of block and move the ray box until angle of refraction is 90. Measure angle i=critical angle. Repeat.

Question 5

Figure 5 shows a way of projecting a small trolley up a sloping track, when a button is pressed, a spring is released in P that projects the trolley up the track. The trolley travels up the track, stops and then rolls back down. The spring in P always exerts the same force when projecting the trolley. A student investigates how the mass of the trolley affects the maximum vertical height reached by the trolley. State the measurements the student should make to complete the investigation.

Answer 5

Measure the mass of the trolley using a balance. Measure the vertical height reached by the trolley with a ruler and repeat for range of masses. Identify the height using a high speed camera. Repeat readings for each mass for an average.

Question 6

Students clapping their hands together to measure speed of sound, explain some ways in which they could improve this experiment.

Answer 6

Increase distance for a more measurable time and improve accuracy. Use datalogger to remove human reactions time and get an improved accuracy.