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Power of a car

Calculate the power of car engine required to drive the car at a speed of 100mph (44.7m/s) against 1400N of resistive force.
Totally confused would really appreciate any help
Reply 1
Original post by Maggie124
Calculate the power of car engine required to drive the car at a speed of 100mph (44.7m/s) against 1400N of resistive force.
Totally confused would really appreciate any help


Power is force * velocity. You must have covered it?
(edited 6 months ago)
Reply 2
So to maintain a constant velocity you need to have a resultant force of 0. Therefore the engine needs to deliver 1400N.

The equation for motive power is:
Power = Force x Velocity
Power = 1400N x 44.7ms^-1
Power = 62580 W
So thats 62.6kW to 3 significant figures :smile:
Reply 3
Thank you so much we probably covered it but sometimes I get really confused with the way they ask the questions

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