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Homework Help: Mechanic about wood block, friction and pulley

  1. Oct 16, 2012 #1
    1. The problem statement, all variables and given/known data
    Two objects A and B weighing 50 N and 80 N respectively were connected by a light string over a fixed pulley. A was put on a reasonably long and horizontal table surface. The coefficient of sliding friction between A and the table surface is μ = 0.3 while the friction between the string and the pulley is neglected. Find the velocity of B after falling downwards for 2m. (Take g = 10 ms^-2)
    Wa = 50 N
    Wb = 80 N
    μ = 0.3

    3. The attempt at a solution
    The question given that the object B falls when at start, thus when object B falls the tension change as the angle change, cant even start the 1st equation.

    Attached Files:

  2. jcsd
  3. Oct 17, 2012 #2
    any1 can help?? i still cant figure how to do this, this question is past year exam question but there's only answer provided. the ans is 2√2
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