Question

A human runner has an average acceleration of 1.2m/s². They ran for a total of 21s. What is the change in their velocity?Mr. Johnson was climbing a roof attempting to fix his gutter system. Without looking he stepped off. Luckily for him his roof is 4.6 meters tall. How long did it take for Mr Johnson to hit the ground? (hint: 9.81 m/s² is acceleration due to gravity.)

Answer 1

The change in velocity for the runner is 25.2 m/s.

In order to find the change in velocity, we can use the formula:
Change in velocity = acceleration * time

Given the average acceleration of 1.2 m/s² and the total time of 21s, we can substitute these values into the formula:

Change in velocity = 1.2 m/s² * 21s = 25.2 m/s

Therefore, the change in velocity for the runner is 25.2 m/s.