Question

In the first 2 seconds of a race, an athlete accelerates constantly from 0 m/s and reaches a
speed of 9 m/s.
Calculate the acceleration of the athlete. You do not need to state the unit here.​

Answer 1

Given :

Initial speed, u = 0 m/s.

Final speed, v = 9 m/s.

Time taken to reach that speed, t = 2 sec.

To Find :

The acceleration of the athlete.

Solution :

We know, in uniform acceleration motion :

$v= u+at\\\\a = \dfrac{v-u}{t}\\\\a = \dfrac{9-0}{2}\ m/s\\\\a = 4.5 \ m/s^2$

Therefore, acceleration of the athlete is 4.5 m/s².