Physics Impulse

Question

A car has a momentum p_x(t) = 3000 N*s - (200 N*s^2)/(t+1.00s).  Find the net force acting on the
car at t = 4.00 s

Answer 1

The net force is the time rate of change of linear momentum.

 

p_x(t) = 3000 - 200/(t + 1), p_x in N*seconds, t in seconds

 

F_x(t) = dp_x/dt = 200/(t + 1)²

 

F_x(4.00) = 200/(4.00 + 1)² N = 8.00 N