Elevator + Counterweight problem

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Homework Statement


The problem is as posted in this picture[/B]

Hey guys/girls, my teacher gave us this problem which I am not sure if I have correct. Could someone please verify if my solution is correct.
Diagram of a counterweight elevator system: a main rotor pulley with a cable running to an elevator car labelled 1000 kg with two people inside, and a counterweight labelled 1350 kg on the other side; the height between is marked 50 m.

Homework Equations



As in my attempt

The Attempt at a Solution


My attempt is scanned -
Handwritten worked solution on lined paper: required acceleration a = 2.5 m/s², free-body diagrams for the car and counterweight with forces 17167.5 N and 13243.5 N, equations for F_car = 21.54 kN and F_counter = 9.8685 kN, and rotor torque and power calculations.
 
Welcome to PF!

Your solution is correct, but you save time both for yourself and for the helpers if you do the solution symbolically, and plug in the data at the end. You would see that the radius of the rotor cancels.
 
ehild said:
Welcome to PF!

Your solution is correct, but you save time both for yourself and for the helpers if you do the solution symbolically, and plug in the data at the end. You would see that the radius of the rotor cancels.
Thanks!
Ok, I will do it symbolically next time