1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Find force link 3 exerts on link 2

  1. Oct 1, 2008 #1
    1. The problem statement, all variables and given/known data
    A chain consisting of five links, each of mass 0.105 kg, is lifted vertically with a constant acceleration of a = 3.5 m/s2. Find the magnitude of the force that link 3 exerts on link 2.

    2. Relevant equations
    F = ma


    3. The attempt at a solution
    I did:
    F = ma
    FU - (0.105 * 3)(9.8) = (0.105) * 3.5
    FU = 4.19 N

    where FU is the force pulling up, (0.105*3) is the mass of the link's 5, 4, and 3 weighing down on link 2 (mg=weight) and then the mass*accel on the other side.

    This is wrong. why? and how do i get the right answer?
     
  2. jcsd
  3. Oct 1, 2008 #2
    does no one know how to do it? ...if it helps. i found the force required to move the top link at that acceleration to be 6.98 N....at it was the right answer...
     
  4. Oct 2, 2008 #3

    PhanthomJay

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    It looks like your calculation and answer is correct, although you left out a 3 in an apparent typo omission (see above in red). Unless, the links are numbered 1 thru 5 bottom to top, rather than 1 thru 5 top to bottom??
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?