When brakes are applied, the frictional forces start acting on the drum of the wheel. If F is the force of friction and s is the distance travelled by truck or car, then work done against force of friction is at the cost of kinetic energy of vehicles.That is, work done i.e.                    ∴                          Since kinetic energy and the retarding force on both the vehicles are same, therefore both will come to rest after travelling equal distances.