Question

A truck and a car are moving with equal velocity. On applying the brakes both will stop after certain distance, then

• A. Truck will cover less distance before rest
• B. Car will cover less distance before rest
• C. Both will cover equal distance
• D. None of these

Answer 1

Answer: (B)

Car will cover less distance before rest

Answer 2

Stopping distance $= \frac{\text{Kinetic energy}}{\text{Retardins}\mspace{6mu}\text{force}} = \frac{\frac{1}{2}mu^{2}}{F}$

If retarding force (F) and velocity (v) are equal then stopping distance ∝ m (mass of vehicle)

As $m_{\text{car}} < m_{\text{truck}}$ therefore car will cover less distance before coming to rest.