(a)

A particle starts moving right along the horizontal line.

Initially the particle is moving towards right.

Distance travelled by the particle increases with respect to time when it is moving towards right.

Distance travelled by the particle decreases with respect to time when it is moving towards left.

Distance travelled by the particle is same with respect to time when it is standing still.

Observe the graph.

During the time interval , the distance increases from 0 to 3 meters and time interval , the distance increases from 1 to 3 meters.

Hence the particle is moving to right during the time interval and .

During the time interval  , the distance decreases from 3 to 1 meters

Hence the particle is moving to left during the time interval .

During the time interval and , the distance moved by particle remains same.

Hence the particle is standing still during the time interval and .

(b) Graph:

Graph the velocity function by taking time on - axis and velocity on - axis.

(a)

The particle is moving to right during the time interval and .

The particle is moving to left during the time interval .

The particle is standing still during the time interval and .

(b) Graph of the velocity function.

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