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Homework Help: Need help.

  1. Aug 6, 2006 #1
    Free body diagrams
    Draw the direction and magnitude of all the forces acting on the block of mass m when it is:
    (a) Stationary on the incline
    (b) Sliding down the incline with velocity, V
    (c) Sliding on a concave surface with velocity, V.
    All surfaces have friction.

    Attached Files:

  2. jcsd
  3. Aug 7, 2006 #2


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    And what hae you done on the problem? No one is going to do your homework for you.
  4. Aug 7, 2006 #3
    thats true but you didnt have to be so nasty about it, even though i cant talk, sorry
  5. Aug 8, 2006 #4
    this is what I have done and am not sure its correct or not....I am confused...I need it today please check my work..
    uploaded the work on this link..

    http://www.uploadfile.info/uploads/50e7ebf4ec.gif [Broken]
    Last edited by a moderator: May 2, 2017
  6. Aug 8, 2006 #5


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    Please describe the forces invovled - starting with gravity, which acts downward. Consider friction - in which direction does is it oriented?

    If something is not moving, what does that tell one about the net forces?

    What forces are normal? What forces are tangential?
  7. Aug 8, 2006 #6
    please cjeck my work..?
    http://www.uploadfile.info/uploads/dd0c7dcf1d.bmp [Broken]
    Last edited by a moderator: May 2, 2017
  8. Aug 8, 2006 #7


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    I'm afraid these are incorrect. You have all the forces involved; weight, the normal force and the frictional force, now you must determine in which direction they are acting. As Astronuc said, gravity always acts down, that is straight down vertically. In which direction is the normal force always directed? In both cases in which direction to friction act?
    Last edited by a moderator: May 2, 2017
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