Question

During a race, a sprinter increases from 5.0 m/s to 7.5 m/s over a period of 1.25 s. What is the sprinter’s average acceleration during this period? _____m/s/s

Answer 1

acceleration is the rate of change of velocity

the speed has increased from 5 m/s to 7.5 m/s over a period of 1.25 s

the formula to calculate acceleration is as follows

$a = \frac{v-u}{t}$

where a - acceleration

u - initial velocity

v - final velocity

t - time

substituting the values in the equation

$a = \frac{7.5 m/s - 5.0 m/s}{1.25 s} = \frac{2.5}{1.25} = 2$

acceleration is 2 m/s²

Answer 2

Acceleration = Change in Velocity/Time taken
                      = 2.5/1.25
                       = 2m/s^2 (or 2m/s/s)