GCSE Physics Exam

Source: OCR June 2003. Reproduced with permission.

5. Tom cycles to school each morning along a straight flat road.

The graph shows his speed for the first 18 seconds of his journey to school.

(a) During the first 8 seconds of the journey, Tom's acceleration was constant.

(i) How can you tell this from the graph? [1]

(ii) Calculate his acceleration during this 8 s period.

You must show how you work out your answer, including any equation used.

acceleration = .......... unit = .......... [4]

(iii) In the first 8 seconds, Tom travelled about 13 m.

Describe how this could be worked out using the graph. [1]

(b) Tom and his bicycle have a combined mass of 60 kg.

(i) Calculate the total kinetic energy of Tom and his bicycle after 10 s.

You must show how you work out your answer and any equation used.

kinetic energy = .......... J [3]

(ii) On another morning, Tom reaches a speed of 1.5 m/s after only 1 second of his journey.

Calculate the average force needed for Tom to reach this speed after 1 second.