John pushes his 1200 kg car from behind with 400 N of force. The coefficient of the rolling friction is 0.03. If he started from rest, how fast is the car going after 30 s of pushing?

Question

John pushes his 1200 kg car from behind with 400 N of force. The coefficient of the rolling friction is 0.03. If he started from rest, how fast is the car going after 30 s of pushing?

Answer 1

John pushes his 1200 kg car from behind with 400 N of force. The coefficient of the rolling friction is 0.03. If he started from rest, how fast is the car going after 30 s of pushing?

Force Applied = 400 N

Force of friction = μ Mg = 0.03 * 1200 *g

Using g = 10m/s2 ( approx)

Force of friction = 360 N

Net force = 400 -360 = 40 N

Acceleration = Force / mass = 40 /1200 = 1/30 m/s2 =0 .033m/s2

Using V = u +at

u= 0 , a= 0.033 , t= 30 s

V = 0.033 * 30 = 0.99 m/s