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Question On A Problem Don't Agree With Teacher

  1. Dec 12, 2006 #1
    Basic Physics stuff nothing too complex...

    #1. A clerk lifts a box 1m vertically. He also slides the box to an equal height over a 2m ramp. How much more force does it take to lift the box vertically?
    He stated that it would take something like twice as much(can't remember if this was it but doesn't really matter with my argument.) What I was arguing was the fact that we cannot tell how much force it takes to slide up the ramp due to the fact we have no coefficient of friction.

    For example...
    Would it take more force to lift a box or try to slide that same box over a ramp thats covered with tar or something with a very high coefficient of friction?

    I put not enough info as my answer and am wondering how on earth that cannot possibly be conceived as a correct answer...
    Thanks in advance...
  2. jcsd
  3. Dec 12, 2006 #2


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    You are correct that you cannot compare the forces unless the coefficient of friction is known. If the ramp is frictionless, it would take twice as much force to lift the box as it would to slide it up the ramp. The problem should have stated it was a frictionles ramp if that was intended.
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