9709 P42 - Jun 2016 - Q6
3443
A car of mass 1100 kg is moving on a road against a constant force of 1550 N resisting the motion.
(i) The car moves along a straight horizontal road at a constant speed of 40 m s-1.
- Calculate, in kW, the power developed by the engine of the car. [2]
- Given that this power is suddenly decreased by 22 kW, find the instantaneous deceleration of the car. [3]
(ii) The car now travels at constant speed up a straight road inclined at 8° to the horizontal, with the engine working at 80 kW. Assuming the resistance force remains the same, find this constant speed. [3]
