question_answer

A truck and a car are moving with the same kinetic energy on a straight road. Their engines are simultaneously switched off. Which one will stop at a lesser distance?

Answer:

                By work-energy theorem, Loss in K.E. of the vehicle \[=\]Work done against the force of friction x distance or          K.E. \[=f\times s=\mu R\times s=\mu \text{mg s}\] or         \[s=\frac{K.E.}{\text{ }\!\!\mu\!\!\text{  mg}}\] For constant K.E., \[s\propto \frac{1}{m}\] As the truck has more mass than the car, so it will stop in a lesser distance than the car.