Question

Figure shows x-t graph of a particle. Find the time t such that the average velocity of the particle during the period O to t is zero.

Answer 1

Consider the point $B_1$ at = 12 sec
At t=0, S=20 m
And at t=12 sec, S=20 m

So for time interval 0 to 12 sec change in displacement is zero.

$\therefore$ Average velocity = $\frac{\text{displacement}}{\text{time}}=0$
Hence the time is 12s.