A 250-N crate is pulled along a horizontal sidewalk at a constant speed by a rope which makes an angle of 40 degrees with the sidewalk. If a force is 150-N is applied on the rope what is the coefficient of sliding friction?

Question

moongazer · Answer

$$F _{f}= \mu F _{n}$$ 
this is the formula i know and i don't know how to use it in this case

anonymous · Answer

Constant Speed Means No Acceleration which further implies No Net Force.

anonymous · Answer

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