What work must be done to accelerate cars weighing 250 km from rest to a speed of 108 km / h.

Task data: m (mass of the accelerating car) = 250 kg; V0 (initial speed) = 0 m / s; V (required speed) = 108 km / h (SI V = 30 m / s).

The work that will need to be done to accelerate the car will be equal to an increase in its kinetic energy: A = ΔEk = 0.5 * m * (V ^ 2 – V0 ^ 2).

Let’s calculate: A = 0.5 * 250 * (30 ^ 2 – 0 ^ 2) = 112.5 * 10 ^ 3 J (112.5 kJ).

Answer: To accelerate the car to a speed of 108 km / h, work of 112.5 kJ must be done.