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Homework Help: Having a hard time

  1. Oct 5, 2008 #1
    1. The problem statement, all variables and given/known data

    A train traveling at a constant speed rounds a curve of radius 235 m. A chandelier suspended from the ceiling swings out to an angle of 17.5° throughout the turn. What is the speed of the train?

    2. Relevant equations

    a=v^2/r
    use of cosine and sine

    v=2x3.14xr/T

    3. The attempt at a solution

    Not sure what 17.5 degrees tells me about the problem, except its continuing along straight while the train turns. I tried to draw but it really doesn't make much sense to me. Also, even if I did compute using cosine and sine, what would that tell me about the problem except distance? And, I can't find acceleration, velocity, or period without time.
    Any thoughts?
     
    Last edited: Oct 5, 2008
  2. jcsd
  3. Oct 5, 2008 #2

    hage567

    User Avatar
    Homework Helper

    Consider the forces on the chandelier (draw a free body diagram). You will have the tension of the string, and gravity.
     
  4. Oct 6, 2008 #3
    I did that and I guess I can derive T from the triangle, but since T is a unit of time, I would have to cancel the time from both sides. Where is the unit of time in my free body diagram?
     
  5. Oct 6, 2008 #4
    Somebody please help I have to get this done by a deadline!!
     
  6. Oct 6, 2008 #5
    slkdfjklsdkfjjjj!
     
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