Using Newton's Second Law, F = ma, where F is the net force
So the net force is:
F = (6kg)(4m/s^2) = 24N
Since you are applying a horizontal force of 30N, we can find the force of friction by the difference of the net force and the applied force.
30N-24N = 6N
So the net force is:
F = (6kg)(4m/s^2) = 24N
Since you are applying a horizontal force of 30N, we can find the force of friction by the difference of the net force and the applied force.
30N-24N = 6N