Question

A train accelerates from $36\text{km/h}$ to $54\text{km/h}$ in $5\text{s}$ then average acceleration of the train is

• A. $1{\text{m/s}}^2$
• B. $2{\text{m/s}}^2$
• C. $0.5{\text{m/s}}^2$
• D. $1.5{\text{m/s}}^2$

Answer 1

The correct option is A $1{\text{m/s}}^2$

Acceleration of the train is given by
$a=\frac{\Delta v}{\Delta t}$
Here, $\Delta v=(54-36)=18\text{km/h}=\frac{18\times 1000}{3600}=5\text{m/s}$
and $\Delta t=5\text{s}$
$\Rightarrow a=\frac{5}{5}=1{\text{m/s}}^2$