Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Elevator problem

  1. Feb 23, 2007 #1
    A system of pulleys is used to lift an elevator that weighs 3900 newtons. The pulley system uses 9 ropes to support the load. How far would 10700 joules of input work lift the elevator? Assume the pulley system is frictionless.

    2. Relevant equations

    3. The attempt at a solution
    and so i tried to solve for f using f=ma...i found m using w=mg (3900=m*9.81=397.55) but we're not given the acceleration so i'm stuck!
    Last edited: Feb 23, 2007
  2. jcsd
  3. Feb 24, 2007 #2
    You have the weight of the elevator. So f=3900N? Try that.
  4. Feb 24, 2007 #3
    then what do i do with the 9 because there are 9 ropes?
    ...maybe multiply it??
  5. Feb 24, 2007 #4
    nvm i got it...you just ignore the 9 ropes
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook