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Mechanics 1 - Edexcel Help.

020200

Hi,

I am having some trouble on this question on forces. Why has the mark scheme got Force Q acting from a point that doesn't originate from the from the particle? I am just having trouble understanding how this mechanism is going to work. Could someone please explain?

Thanks!

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Reply 1

old_engineer

Original post by DhylanP - CRGS

This simply arises from the usual way (or at least one of the usual ways) of adding vectors, which is to join them up end to end. The resultant force can then be drawn as a straight line between the start of the first vector and the end of the last vector.

An alternative construction is the parallelogram of forces. For this, you would draw P and Q starting at the same point then complete the parallelogram with lines parallel to, and equal in length with, P and Q. The resultant force is then the diagonal of the parallelogram.