(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

(a) A block with a mass m is pulled along a horizontal surface for a distance x by a constant force vector F at an angle θ with respect to the horizontal. The coefficient of kinetic friction between block and table is μk. Is the force exerted by friction equal to μkmg?

ANSWER = No (Correct )

Enter the expression that describes only the magnitude of the force exerted by friction. (Use any variable or symbol stated above along with the following as necessary: g and F for the magnitude of vector F .)

fk = ?

(b) How much work is done by the friction force and by vector F ? (Don't forget the signs. Use any variable or symbol stated above along with the following as necessary: g and F for the magnitude of vector F .)

Wfk = ?

WF =?

3. The attempt at a solution

fk= μk (mg-Fsin(θ))

Wfk=-(cos(θ))d

WF=mg(sin(θ))d

*d= distance

I'm struggling coming up with the correct equations. Any help is appreciated.

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# Homework Help: Equations for fk, Wfk, and WF as an expression

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