Answer:
13.41 horsepower
Explanation:
Power: This can be defined as the rate at which energy is used up by a body. The S.I unit of power is Watt (W).
The expression for power is given as,
P = Ek/t...................... Equation 1
Where P = power, Ek = Kinetic Energy of the car, t = time.
Recall that,
Ek = 1/2mΔv²............ Equation 2
Where m = mass of the car, Δv = change in velocity of the car.
Substitute equation 2 into equation 1
P = 1/2(mΔv²)/t...................... Equation 3
Given:m = 1000 kg, Δv = 30-20 = 10 m/s, t = 5 s
Substitute into equation 3
P = 1/2(1000×10²)/5
P = 10000 W.
If,
745.7 W = 1 hp,
Then,
10000 W = (10000/745.7) hp
= 13.41 hp.
P = 13.41 horsepower
