6 exam-style questions with full mark schemes and model answers. Write your own answer and the AI examiner marks it against the mark scheme.
A skydiver jumps from a stationary helicopter and falls towards the ground. At first she speeds up, but eventually she falls at a steady (terminal) velocity before she opens her parachute.
Explain, in terms of the forces acting on her, why the skydiver first accelerates, then reaches a constant terminal velocity. Refer to weight and air resistance and to how the resultant force changes during the fall. (6 marks)
A student investigated Hooke's law by hanging weights from a spring and measuring its extension (a required practical). The unstretched length of the spring was 8.0 cm. The results are shown below.
| Force / N | Length of spring / cm | Extension / cm |
|---|---|---|
| 0 | 8.0 | 0 |
| 2.0 | 10.0 | 2.0 |
| 4.0 | 12.0 | 4.0 |
| 6.0 | 14.0 | 6.0 |
| 8.0 | 16.0 | 8.0 |
(a) State how the extension is calculated from the measured length of the spring. (1 mark)
(b) Calculate the spring constant, in N/m. Use F=ke and remember to convert the extension to metres. Show your working and give the unit. (3 marks)
A car of mass 900 kg experiences a resultant forward force of 3600 N from its engine.
(a) Calculate the acceleration of the car. Use F=ma. Show your working and give the unit. (2 marks)
(b) The car has a weight. Calculate the weight of the car. Use W=mg with g=9.8 N/kg. (1 mark)
This question is for Higher tier.
A trolley of mass 1.5 kg is moving in a straight line at a velocity of 4.0 m/s.
(a) Calculate the momentum of the trolley. Use p=mv. Show your working and give the unit. (2 marks)
(b) A second, identical trolley of mass 1.5 kg is stationary. State the momentum of this stationary trolley, and give a reason for your answer. (1 mark)
The stopping distance of a car is made up of the thinking distance and the braking distance.
State one factor that increases the thinking distance and one different factor that increases the braking distance of a car. (2 marks)
Physical quantities can be classified as scalars or vectors.
State the difference between a scalar quantity and a vector quantity. (1 mark)