Asimple model for a person running the 100 m dash is to assume the sprinter runs with constant acceleration until reaching top speed, then maintains that speed through the finish line. if a sprinter reaches his top speed of 11.2 m/s in 2.14 s, what will be his total time?

He will complete the race in total time of T = 10 s

Explanation:

Total distance moved by the sprinter in 2.14 s is given as

now the distance remaining to move

now he will move with uniform maximum speed for the remaining distance

so we will have

so the total time to complete the race is given as

we need to know the time interval during which the force acts. impulse of force = momentum change

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.