What is the maximum mass that this motor can lift at an average speed of 3 m/s? (show work on how to get an answer)
Power = work ÷ time
Work = Force * Distance
Power = Force * distance ÷ time
Power = Weight * Speed
Since the elevator rises at an average speed, this equation can be used to determine the maximum weight this motor can lift.
8.1*10^4=Weight*3
Weight = 8.1 * 10^4 ÷ 3 = 2.7 * 10^4 N
The motor can produce F = P/v = 8.1E4/3 = 2.7E4 Newtons of lifting force. But there will be friction and shedding, so the maximum weight the lift can lift will be less than this value. RES.
Power = energy/time change
Energy change is PE, m*g*h
Power = m*g*h/t
Separate
Power = (m*g)*(h/t)
Set as follows
M*g = weight
H/t = vertical speed
Climb and adjust the weight
power = weight*v
Weight = power/v = 81,000 W / 3 m/s = 27,000 N
Ready!
P=W/t=Fv
81000W=F(3)
81000/3=F
F=27000N or 2.7 × 10^4N
As the lift is included in the maximum weight, this is the answer.
assuming 100% efficiency
m = (p * e) / (g * v)
m = (81000 * 1) / (9.81 * 3)
m = 2752.29 kg <=== year