Two cars are travelling towards each other at a speed of $20 \,m \,s^{-1}$ each. When the cars are $300 \,m$ apart, both the drivers apply brakes and the cars retard at the rate of $2 \,m \,s^{-2}$. The distance between them when they come to rest is: (in $\,m$)

$A$ man is $45 \, m$ behind the bus when the bus starts accelerating from rest with an acceleration of $2.5 \, m/s^2$. With what minimum velocity should the man start running to catch the bus?

Explain the concept of relative velocity and its two cases.

$A$ police party is moving in a jeep at a constant speed $v$. They see a thief at a distance $x$ on a motorcycle which is at rest. The moment the police see the thief, the thief starts moving with a constant acceleration $a$. Which of the following relations is true if the police are able to catch the thief?

$A$ car $A$ is travelling on a straight level road with a uniform speed of $60 \text{ km/h}$. It is followed by another car $B$ which is moving with a speed of $70 \text{ km/h}$. When the distance between them is $2.5 \text{ km}$,the car $B$ is given a deceleration of $20 \text{ km/h}^2$. After how much time will $B$ catch up with $A$ in hours?

$A$ man on a rectilinearly moving cart,facing the direction of motion,throws a ball straight up with respect to himself.