Question

Acceleration-time graph of a particle moving in a straight line is shown in Fig. 3.19. Velocity of particle at time t=0 is 2 m/s. Find velocity at the end of fourth second.

Answer 1

Given : $V_i=2m/s$ at $t=0$ s

Let $V_f$ be the velocity of the particle at $t=4$ s

Area under the a-t graph gives the change in velocity of the particle during that period.

$\therefore$ $\Delta V=V_f-V_i=\frac{1}{2}\times 4\times 4=8$

OR $V_f-2=8$ $⟹V_f=10m/s$