A bus moving along a straight highway with speed of $72 \mathrm{~km} / \mathrm{h}$ is brought to halt within $4 s$ after applying the brakes. The distance travelled by the bus during this time (Assume the retardation is uniform) is _____m.

Question

Aicharya · Accepted Answer

$\begin{aligned} & 	ext { Initial velocity }=u=72 \mathrm{~km} / \mathrm{h}=20 \mathrm{~m} / \mathrm{s} \ & \mathrm{v}=\mathrm{u}+	ext { at } \ & \Rightarrow 0=20+\mathrm{a} 	imes 4 \ & \mathrm{a}=-5 \mathrm{~m} / \mathrm{s}^2 \ & \mathrm{v}^2-\mathrm{u}^2=2 	ext { as } \ & \Rightarrow 0^2-20^2=2(-5) . \mathrm{s} \ & \mathrm{s}=40 \mathrm{~m}\end{aligned}$

A bus moving along a straight highway with speed of $72 \mathrm{~km} / \mathrm{h}$ is brought to halt within…

Solution