Answer:
7.92 s
Explanation:
Power: This can be defined as the rate at which energy is used. The S.I unit of
Watt (W).
Mathematically power can be represented as,
P = E/t
Pt = E............................. Equation 1
Where P = power of the engine, t = time, E = Energy.
But,
E = 1/2m(Δv)²................. Equation 2
Where m = mass of the automobile, Δv = change in velocity of the car = final velocity - initial velocity.
Substitute the value of E in equation 2 into equation 1
Pt = 1/2m(Δv)²................................. Equation 3
making t the subject of the equation,
t = 1/2m(Δv)²/P ........................ Equation 4
Given: m = 1540 kg, P = 75 kW = 75000 W, Δv = 100-0 = 100 km/h (initial velocity of the car = 0 km/h)
100(1000/3600) m/s = 27.78 m/s
Substitute into equation 4
t = 1/2(1540)(27.78)²/75000
t = 594230.87/75000
t = 7.92 second.
Thus The time required to accelerate the car = 7.92 seconds.
It is not realistic period the time period is too short.
