Question

A truck starts from rest with an acceleration of $1.5{\text{m/s}}^2$ while a car 150 m behind the truck starts from rest win an acceleration of $2{\text{m/s}}^2$. How long will it take before both the truck and car meet?

• A. $31.7\text{s}$
• B. $24.5\text{s}$
• C. $17\text{s}$
• D. $12\text{s}$

Answer 1

The correct option is B $24.5\text{s}$

Answer (2)
Acceleration of car relative to truck
$=2-1.5=0.5{\text{m/s}}^2$
Now, time taken to melt
$t=\sqrt{\frac{2\times 150}{0.5}}=24.5\text{s}$