A car of mass travels along a level road with a uniform speed of
PHYSICS · Multi-part · AP · Physics C: Mechanics · Force and Translational Dynamics · Force and Translational Dynamics
Problem
A car of mass 1200kg travels along a level road with a uniform speed of 108km h−1. While moving, it experiences an air resistance of 400N and a rolling resistance of 200N acting opposite to its motion.
(i) Calculate the magnitude of the horizontal driving force that the engine must supply to maintain this speed.
(ii) If the driver shifts to neutral so that the engine delivers no driving force, determine the magnitude of the car’s deceleration immediately after this action. Assume the resistive forces remain unchanged and take g=9.8m s−2.