A sprinter runs 50m. You are given a stopwatch. Describe how you would measure: 1. the average speed of the sprinter over the entire 50m

2. the instantaneous speed of the sprinter when he crosses the finish line

Distance = 50 m

1. To find the average speed, first start the stop watch as the sprinter starts running and then stop it when he reaches the finish line.

Now note the time taken by the sprinter to run for 50 m.

The average speed of the sprinter is defined as the ratio of total distance covered to the total time taken.

Average speed = total distance / total time

2. To find the instantaneous speed, check the seed of the sprinter as he is at the finish line.