9709 P43 - Nov 2021 - Q4 - 9 marks
3408
A car of mass 1400 kg is moving on a straight road against a constant force of 1250 N resisting the motion.
Use \(g=10\mathrm{\ m\,s^{-2}}\).
(a) The car moves along a horizontal section of the road at a constant speed of 36 m/s.
(a)(i) Calculate the work done against the resisting force during the first 8 seconds. [2]
(a)(ii) Calculate, in kW, the power developed by the engine of the car. [2]
(a)(iii) Given that this power is suddenly increased by 12 kW, find the instantaneous acceleration of the car. [3]
(b) The car now travels at a constant speed of 32 m/s up a section of the road inclined at θ° to the horizontal, with the engine working at 64 kW. Find the value of θ. [2]
