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Homework Help: Finding Average Power

  1. Oct 10, 2004 #1
    If a ski lift raises 100 passengers averaging 656 N in weight to a height of 145 m in 60 s, at constant speed, what average power is required of the force making the lift?

    I know average power is P=W/t, where W is work and t is change in time. Since work is w=fd, I did 656 N*145 m and then took that number and multiplied it by 100 for the 100 passengers. I then took this product and divided it by the change in time, 60 seconds, and I got 158533 W for the average power, and it's wrong. Am I just misunderstanding the problem, or am I really doing this wrong?
     
  2. jcsd
  3. Oct 10, 2004 #2
    I think u r right! unless i missed the same thing u missed!

    -- AI
     
  4. Oct 10, 2004 #3
    lol well the answer is wrong so I don't know. :mad:
     
    Last edited: Oct 10, 2004
  5. Oct 10, 2004 #4
    I even tried not multiplying by 100 and it's wrong :cry:
     
  6. Oct 10, 2004 #5
    ok, heres what ya do....
    P=(F)(V)
    P=(W)(V)
    P=(100)(656)(145/60)
    thats how i did it
     
  7. Oct 10, 2004 #6
    Oh gosh I was doing that and I wound up putting 1585.33 instead of 158533 lol dumb mistake good thing I got it :) Thanks
     
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