A man on a bosun chair

  1. A man is on a bosun chair attached to a frictionless massless pulley and is holding onto the other end of a rope. (at ground level)

    a. What is the force he must pull himself up at if he is to move at a constant speed?
    Is the set up T + T = mg?

    b. If instead the rope is held by someone else, what is the force needed to pull him up at a constant speed?

    And is this set up as T = mg?

    c. What is the force exerted by the ceiling on the system for both cases?

    This one I am lost on since I need to do a free body diagram for each case.

    I dont understand why there is such a difference, in essence.
     
  2. jcsd
  3. Chi Meson

    Chi Meson 1,772
    Science Advisor
    Homework Helper

    a and b, you are correct. In a, there are "two tensions" pulling up on the guy in the sling. In b, there is only one tension pulling on the guy.

    c:

    how many tensions are pulling down on the pulley?
     
  4. Draw a free body diagram from the pulley. That should help.
     
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