A man is trying to move a couch with a mass of 200 kg, across a rug covered floor.(adsbygoogle = window.adsbygoogle || []).push({});

He must use an exert force 0f 700 N to get it to barely move. His daughter has estimated that once it moves, then it accelerates at 1.10 m/s^2

determine:

a) coefficient of static friction

b) coefficient of kinetic friction between couch and the rug.

I dont even know what units i should use and what formula is generally given. the section for friction gives like 20 diff units to use but doesn't tell which to use.

please help me understand-i dont want to know the answer-i want to know how to do it!

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also another one-how do you find an object's acceleration if you are given only one angle and force (ie-object of 10kg is sliding upward on a vertical wall with force of 60 and angle at 60. what is the normal force and the object's acceleration)

^^ for the normal force exerted i used:

F cos 60 = 60 cos 60 = 30 N <--does this apply to the latter question??

thanks alot!!

:D

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# Homework Help: Static/kinematic friction trouble !

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