A man moves in $x$-$y$ plane along the path shown. At what point is his average velocity vector in the same direction as his instaneous velocity vector. The man starts from point $P$.

What of the following velocity-time graph shows a realistic situation for a body in motion:

a)               b)

The graph between the displacement $x$ and time $t$ for a particle moving in a straight line is shown in figure. During the interval $OA,AB,BC$ and $CD$, the acceleration of the particle is:

The velocity-time graph of a body falling from rest under gravity and rebounding from a solid surface is represented by which of the following graphs?

The acceleration-time graph of a particle moving along a straight line is as shown in figure. At what time the particle acquires its initial velocity?

Which of the following situation may be represented by the velocity-time graph as shown in the diagram