Question

A body starts from rest and with a uniform acceleration of $10m{s}^{-2}$ for 5 seconds. During the next 10 seconds it moves with uniform velocity. The total distance travelled by the body is :-

• A. $100m$
• B. $125m$
• C. $500m$
• D. $625m$

Answer 1

Answer: (D)

$625m$

The initial velocity travelled is $625$m

The accleration is $\alpha =10m/s^2$

The time is $t=5s$

Apply the equation of motion

$v=u+at$

The velocity is $v=0+10.5=50m/s$.

The distance travelled in the first $5s$ is

$\begin{array}{c}s=ut+\frac{1}{2}a{t}^2\\ =0.5+\frac{1}{2}.10{.5}^2=125m\\ Thedis\tan cetravelledinthefollowing10sis\\ s_1=u{t}_1=50.10=500m\\ Thetotaldis\tan cetravelledis\\ d=s+s_1=125+500=625m\end{array}$