When are forces negative or positive in physics problems?

SS2006 · Oct 13, 2005

im always confued about negative and positive signs, soemone give em a easy way to remember
is whatever is on the left side of the x-axis egative, and above positive always?
also when is friction negative, if the mass if moving up a ramp, is friction always negative, and if its moving down, its postitive?
thanks

nbo10 · Oct 13, 2005

Friction always action in the opposite direction of the applied force. coordinate system is arbitary you can define positive or negative any way you want.

When are forces negative or positive in physics problems?

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When are forces negative or positive in physics problems?

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