Question

The velocity-time graph of a body is given in figure. The maximum acceleration in ${\text{ms}}^{-2}$ is

• A. $4$
• B. $3$
• C. $2$
• D. $1$

Answer 1

The correct option is A $4$

Acceleration from $0$ to $20\text{s}$ will be
$a=\frac{v_2-v_1}{t_2-t_1}=\frac{20-0}{20-0}=1$ Acceleration from 20 to 30 s will be
$a=\frac{v_2-v_1}{t_2-t_1}=\frac{20-20}{30-20}=0$
Acceleration from 30 to 40 s will be
$a=\frac{v_2-v_1}{t_2-t_1}=\frac{60-20}{40-30}=4$
Acceleration from 40 to 70 s will be
$a=\frac{v_2-v_1}{t_2-t_1}=\frac{0-60}{70-40}=-2$
So, maximum acceleration will be from $30$ to $40\text{s}$, because slope in this interval is maximum $a=4{\text{m/s}}^2$