(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A fully loaded freight elevator has a cab with a total mass of 1490 kg, which is required to travel upward 58

m in 2.1 minutes, starting and ending at rest. The elevator's counterweight has a mass of only 985 kg, so the

elevator motor must help. What average power is required of the force the motor exerts on the cab via the cable?

2. Relevant equations

F=ma

W=F * D D= displacment (distance traveled)

P = W/t P= power, t = time

v=u + at u = initial velocity, v = final velocity

v^2 = u^2 +2aD

D= ut + 1/2(a)t^2

3. The attempt at a solution

I have tried to solve for a by using the formula D= ut + 1/2(a)t^2 then taking that a and multiplying it with the mass then multiplying that by distance and then dividing by the time needed to be done but i can't get it right and i feel like i should do something with the counterweight but i dont know what any thing will help thank you

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# Homework Help: Work done by motor pulling up elevator

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