how to draw a pulley in svg?
I want to draw a pulley shown under "Standard Pulley Problem" title at http://www.sparknotes.com/testprep/books/sat2/physics/chapter8section2.rhtml in svg and want to take values for m and M from user using javascript. how can i do that? 
 
how to draw a pulley in svg?
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I want to draw a pulley shown under "Standard Pulley Problem" title at http://www.sparknotes.com/testprep/books/sat2/physics/chapter8section2.rhtml in svg and want to take values for m and M from user using javascript. how can i do that? 
 