What is the maximum weight this motor can lift at an average speed of 3 m/s? (show work on how to get answer)

**Answer 1**

Power = Work ÷ time

Work = Force * distance

Power = Force * distance ÷ time

Power = Weight * Velocity

Since the elevator is moving upward at a 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

**Answer 2**

The motor can produce F = P/v = 8.1E4/3 = 2.7E4 Newtons of lifting force. But there will be friction and losses, so the max weight the lift can lift will be something less than that value. ANS.

**Answer 3**

Power = change in energy / time

The energy changing is PE, m*g*h

Power = m*g*h/t

Separate

Power = (m*g)*(h/t)

Define as follows

M*g = weight

H/t = vertical speed

Sub in and solve for weight

Power = weight*v

Weight = power/v = 81000 W / 3 m/s = 27000 N

Presto!

**Answer 4**

P=W/t = Fv

81000W=F(3)

81000/3= F

F=27000N or 2.7 × 10^4N

Since elevator in included in max weight, this is the answer.

**Answer 5**

assuming 100% efficiency

m = (p * e) / (g * v)

m = (81000 * 1) / (9.81 * 3)

m = 2752.29 kg <===ans