If the displacement $-$ time graph for a particle is parallel to the time axis, what is the velocity of the particle?

If the acceleration of a particle is constant in magnitude but not in direction,what type of path is followed by the particle?

An object is moving with uniform speed in a circle of radius $7 \, m$. Calculate the distance and displacement when it completes half the circle. What type of motion does the object possess?

Answer the following questions:
$(i)$ State the type of motion shown by a freely falling stone.
$(ii)$ When a stone is thrown vertically upwards,its velocity is continuously decreased. Why?
$(iii)$ Give an example of a motion in which average velocity is zero,but the average speed is not zero.

The direction of acceleration of an object moving in a circular path is

The velocity-time graph (Fig.) shows the motion of a cyclist. Find $(i)$ its acceleration $(ii)$ its velocity and $(iii)$ the distance covered by the cyclist in $15\,s$.