Two students want to determine the mean speed of runners during a 100-meter sprint on their school's track.
a.[3]
Describe how the students can take the measurements they need to calculate the mean speed of a runner during the sprint.
b.[2]
The students also investigate the motion of two electric toy scooters, P and Q, as they accelerate from rest. The velocity–time graph shows their results.
Which scooter, P or Q, has the greater acceleration? Explain your answer.
c.[2]
Use the graph to calculate the acceleration of scooter Q.
d.[1]
Both scooters have the same mass. Suggest why it takes different amounts of time for them to reach their top speed.