1. A car of mass 1100 kg starts from rest at sea level and climbs a hill of altitude 50 m. At the top of the hill the car has a speed of 25 m/s. From the top of the hill the driver turns off the engine and coasts down to an altitude of 15 m. Assume the friction and the air resistance to be negligibly small.(adsbygoogle = window.adsbygoogle || []).push({});

a. work produced by the engine of the car?

b.Speed of the car when the altitude is 15m

c. After passing the altitude of 15m, the driver climbs up again, without turning the engine on. In this case, the speed of the car would be zero

at an altitude of?

d. In reality the friction and the air resistance are not zero. If the work needed to overcome thefriction and the air resistance is 5.2×105 Joules, the answer to part (a) would change. In thiscase, the work produced by the engine to climb to 50 m and have a speed of 25 m/s at the topwould be?

e. In part (d) the car reaches the top of the hill in 80 seconds. The power developed by the

engine is?

I have the answers, I am just confused where to start and what equations to use. Please help me get started on these!!

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# Homework Help: So confused

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