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Newton's Laws questions?

  1. Jul 6, 2011 #1
    Hey, I have a question I'm stuck on for my grade 12 physics class. There is a block being pulled by tension over a triangle essentially that's at a degree of 35.7 (right angle triangle). I understand the whole question but I don't understand how to find how much pull the block has backwards of it's acceleration? It says it's the mass x gravity x sin 35.7. Why is sin theta added in there? Sorry if this is difficult to understand, if I could draw the picture, this would be so much easier. Thanks if anyone understands my question/can help me out.
  2. jcsd
  3. Jul 6, 2011 #2

    Doc Al

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    Staff: Mentor

    They found the component of the gravitational force parallel to the incline. Read this: http://www.physicsclassroom.com/Class/vectors/u3l3e.cfm" [Broken]
    Last edited by a moderator: May 5, 2017
  4. Jul 6, 2011 #3
    Oh alright, I understand it now, thank you. I didn't think of it that way :biggrin:
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