Question Constellation Sign up for free AQA · GCSE · Combined Science · Higher
Changing speed during a race
Explain why the speed of a competitor changes during the race.
Write your answer first. You can study the marking guidance whenever you need it.
Study the marking See what earns credit and compare it with a full-mark answer.
Marking points
- 1 Give at least one relevant cause of a speed change during the race.
- 2 Link each cause to a consistent effect on speed, such as increased speed downhill or decreased speed uphill.
- 3 Develop the explanation with detailed, logically linked cause-and-effect points rather than just listing causes.
- 4 Credit examples can include accelerating at the start, hills, bends, tiredness, sprinting, punctures, or changes in resistive forces, provided the stated speed change matches the cause.
Full-mark answer
A competitor’s speed changes because the forces and conditions change during the race. At the start the competitor accelerates, so their speed increases. If the road goes uphill they slow down, and if it goes downhill they may speed up. Towards the end they may tire and exert less force, so their speed decreases.
Why this answer loses marks
They go uphill so speed increases.
The effect is not consistent with the cause; going uphill would normally decrease speed.