Question

An athelete takes $2.0s$ to reach his maximum speed of $18.0km/h$ after starting from rest. What is the magnitude of his average acceleration?

• A. $2.5m/s^2$
• B. $7.5m/s^2$
• C. $9.5m/s^2$
• D. $12.5m/s^2$

Answer 1

The correct option is A $2.5m/s^2$

Average acceleration $\left(a\right)=\frac{v-u}{t}$

where, v = final velocity $=18km/h=5m/s$

u= Initial Velocity $=0km/h=0m/s$

And, t=time taken

So, $a=\frac{5-0}{2}=2.5m/s^2$