Question

Acceleration-time graph of a particle moving in a straight line is as shown in the figure. At time $t=0$, velocity of the particle is zero. Find velocity of the particle at $t=14$s:

• A. 90 m/s
• B. 10 m/s
• C. 9 m/s
• D. 50 m/s

Answer 1

The correct option is A 90 m/s

We know that the velocity is given by the area under the acceleration-time graph.

Hence at $t=14s$, $v=10\times 4+\frac{1}{2}(10+20)\times 2+\frac{1}{2}\times 4\times 20-\frac{1}{2}\times 4\times 10$

$⟹v=40+30+40-20$

$⟹v=90m/s$