# Physics

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The co-efficient for static friction for a 5 kg box on a floor is .72. How much force if required to start the box sliding?
I worked it as follows:
Force of friction=Force normal * co-effic. of friction which is .72*5*9.8=35.28 but answer in back of my book says this is wrong. Where did I err?

• Physics -

Force of Friction= Force of the normal*co-effic...

Coefficient= .72
Normal Force= mass*g
9.81*5
49.05
Solve: 49.05*0.72
35.316 or 35.32

Is that what you got? If it is, you're right. If not, recheck the book, it may be that you are looking at the wrong answer.

• Physics -

Yes, that's my answer too. Incorrect answers at the back of the book drive me crazy! thanks for confirming!

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