Practice!

Sample Problem

A force of 8.0 N gives a 1.0 kg block an acceleration of 4.0 m/s2 to the right.

The force of friction acting on the block is N.

Solution

According to Newton’s second law, Fnet = ma.

Fnet = 1.0 kg × 4.0 m/s2 = 4.0 N

f = 8.0 N - 4.0 N = 4.0 N