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

Homework Help: Potential and Kinetic Engery help needed

  1. Oct 27, 2004 #1
    A uniform chain of length 8.00m initially lies stretched out on a horizontal table.

    a) If the coefficient of static friction between the chain and the table is 0.600, show that the chain will begin to slide off the table if at least 3.00m of it hangs over the edge of the table.

    Determine the speed of the chain as all of it leaves the table, given that the coefficient of the kinetic friction between the chain and the table is 0.400.

    I have solved part a no problem. Part b I am having a lot of problems with. I am trying to fill in the equation U(init)+K(init)-W(fric)=U(final)+K(final)

    I understand that the right side is U(final) is 0 and K(final) is 1/2mv^2. How about the left side?

    Thank you in advance
  2. jcsd
  3. Oct 27, 2004 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Don't you have a thread started on this same problem already?

    Here are some hints. If U(final) is zero, where are you measuring PE from? Use that same point to measure the initial PE from. Doesn't the chain start falling from rest? Figure out the work done against friction.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook