A class uses one handheld stopwatch to time a 5 m sprint and claims a runner improved by 0.03 s. Evaluate the claim and propose a stronger measurement method.

Question

Accepted Answer

The claimed change is smaller than typical reaction-time uncertainty; use electronic gates, a longer interval and repeated trials with controlled conditions. Human start and stop reactions are each comparable with or larger than 0.03 s. A single trial gives no evidence of repeatability or natural variation. Use light gates or video timestamps, increase the timed distance, repeat, average and report spread. Keep surface, start method, footwear and recovery time controlled before judging improvement.

Can a stopwatch catch a sprint?

A class uses one handheld stopwatch to time a 5 m sprint and claims a runner improved by 0.03 s. Evaluate the claim and propose a stronger measurement method.

What a complete response should do

How did this one feel?