Power is equal to (Newtons x meters)/time, also known as the following equation...
P = Fd/t
Your force is 1800Newtons and your velocity is 0.4m/s
Velocity is equal to distance/time, also known as the following equation...
v = d/t
So your equation is basically P = Fv
P = 1800N x 0.4m/s
P = 720 Watts
