Answer:
Explanation:
Force - frictional Force = m * a
20N - 5N = 5 * a
15N = 5*a
15N / 5 = a
a = 3 m/s^2
You should note a couple of things.
1. The frictional Force always opposes the direction of motion. In this case it is minus and the 20 N is plus. It makes the acceleration less. If the friction force was not there then 20 N = m * a
20N = 5 kg * a
a = 20/5
a = 4 m/s^2.