Given that,
Mass of elevator + passengers, M=1800Kg
Speed, v=2m/s
Friction force, f=400N
Power delivered, P=force×velocity.........(1)
Force acting downward,
F=mg+f
F=1800×10+4000
F=22000N
Put the value of F in equation (1)
P=22000×2
P=44000Watts