The car starts off with an acceleration of 0.2 ms2 and reaches a speed of 18 km / h.

The car starts off with an acceleration of 0.2 ms2 and reaches a speed of 18 km / h. Determine the work done by the car in this area, if the traction force is 3 kN

a = 0.2 m / s2.

V0 = 0 m / s.

V = 18 km / h = 5 m / s.

Ft = 3 kN = 3000 N.

At -?

We express the work of the traction force of the car Am by the formula: At = Ft * S * cosα. Since the direction of the traction force Ft of the car coincides with the direction of its movement, then ∠α = 0 °.

We express the movement of the car S by the formula: S = (V ^ 2 – V0 ^ 2) / 2 * a.

Since the car starts to move V0 = 0 m / s, the formula will take the form: S = V ^ 2/2 * a.

Am = Ft * V ^ 2/2 * a.

Am = 3000 N * (5 m / s) ^ 2/2 * 0.2 m / s2 = 187500 J.

Answer: on the site, the car does work Am = 187500 J.