Direction of the motion is same as the sign of the velocity.

i.e. positive velocity gives forward motion, negative velocity gives backward motion.

(1): When t=1s, velocity(v) is negative, no matter fefore or after 1s, so the direction of the motion is not changing, so (1) is false.

(2): Displacement is equal to the area under the v-t graph.

At t=2, area under v-t graph of particles P is = (2)(-2)/2 = -2m

Similarly, area under v-t graph of particles Q is 2m

Then, the different between P and Q is = 2-(-2) =4m

So (2) is true.

(3): Similar to (2), we can use the area to find the displacement of two particles.

displacement of P = 2m

displacement of Q = 8m

By comparison, P and Q is not in the same position

So (3) is false.

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