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greenday101
A 25 kg box rests without sliding on a loading ramp at an angle of 30 degrees. What is the coefficient of friction between the box and the ramp? I know the answer is .58 but I'm not sure how to do this.
\[F _{static}=\mu mg\] on a horizontal surface
on an angle... \[F _{static}=\mu mgcos \Theta\] not sure where to go from here without additional info. nothing else was given?
I figured it out. tanΘ=tan(30)=.577