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Homework Help: Tensions involving INCLINE

  1. Oct 12, 2005 #1
    This is the question I was given a homework assignment:

    2) Two objects are connected by a light string that passes over a frictionless pulley. Draw a Free Body Diagram of both objects. If the inclide is frictionless and if m1= 2kg, m2=6kg and angle theta=55 degrees, find:
    (a) the accelerations of the objects
    (b) the tension in the string
    (c) the speed of each object 2 sec after being released from rest.

    **my question is: is the acceleration for both objects the same, just different directions?**

    how do you incorporate the theta 55 degrees into this question?

    Attached Files:

  2. jcsd
  3. Oct 12, 2005 #2


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    Homework Helper

    Yes, the acceleration will be the same. In these problems, unless stated otherwise, we typically assume the string doesn't stretch.
    As for the 55 degree angle, well, think about it. When you draw the FBD, you're going to have some forces that act parallel to the plane, some that act normal to it, and some that are at some angle. You're going to need to resolve them so you have them all following some arbitrary set of axes - you'll need the angle then. Right?

    Edit: About the accelerations - reconsider the "opposite directions" thing. It depends partly on how you're defining the directions, but if you pull on one object, which way will the other one move?
    Last edited: Oct 12, 2005
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