Polygon Of Forces To Demonstrate Equilibrium

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sperrya
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Homework Statement


Use the polygon of forces to demonstrate that a 200 kg crate on a 25o incline is in equilibrium on the slope.


Homework Equations


See attached


The Attempt at a Solution


Please see attached for my attempt, I think I am in the right ball park, just need to know what seat to be in, i.e. how do I plot the answer to satisfy the question. Please help...

Thanks
 
Attachments
  • Handwritten working on a crate on a 25 degree incline: a small sketch of a 200 kg crate on a slope with a 12 m height, then the attempted calculations Mg = 1962 N, Fd = 829.177 N and FN = 1778.176 N, and a force triangle with Mg, Fd and FN labelled and a scale of 1 cm = 200 N.
    IMG_0218.jpg
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  • Handwritten worked solution on lined paper: a 1962 N force at 25 degrees resolved into x = 1778.176 N and y = 829.17 N, then combined to R = 1961.999 N at 24.999 degrees, with a handwritten sketch of the force polygon at the bottom.
    IMG_0219.jpg
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You must draw the force polygon so that the forces show the correct magnitude and direction. For instance, how must the weight vector of the box be drawn?
 
Hi there, thanks for your reply, I know I need to draw a force triangle of some sort, but unsure how to do it with the information I have. Even then, is this a correct polygon of force??

Thanks
 
What direction is the weight force usually drawn?