A 1.00x10^3kg sports car accelerates from rest to 25m/s in 7.5 seconds. What is the average power output of the car?

mass of car = 1000 kg

a = (v - u) / t = (25 - 0) / 7.5 = 3.33 m/s²

actually perhaps this is not required as we can calculate the kinetic energy gained = work done by the car = W = ½mv²

=> ½1000(25)² = 500*625 = 312500 Joules

P = power = work / time = W/t = 312500 / 7.5 = 41666.667 Watts

since 1 bhp ~= 746 W, this ans is ~= 56 bhp

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aliter:

a = 3.33 m/s²

force F producing this acceleration = ma = 1000(3.333) = 3333.33 N

distance covered => s = ut + ½at²

= ½3.333*7.5² = 93.75 m

W = work done = F x s = 3333.33 x 93.75 = 312499.68 J

P = W / t = 312499.68 / 7.5 ~= 41666.62 W ~= 56 bhp

hope this helps