My teacher gave us a homework. We must count the coefficient of kinetic friction between the object and the surface. We can only use the object, ruler and book or table etc. as the surface of motion. We are not allowed to count the acceleration with clock.(adsbygoogle = window.adsbygoogle || []).push({});

I decided to make the object slide by increasing the angle between book(the surface) and table. Finally object started sliding and I measured the angle([tex]\alpha[/tex]). And finally I got: [tex]\mu[/tex]= tan[tex]\alpha[/tex].

G_{x}= sin[tex]\alpha[/tex]*G

Then I realised that the angle [tex]\alpha[/tex] is the angle when G_{x}>F_{f0}(read:the maximum of static friction)

But isn't F_{f}< F_{f0}.

So is this task even possible(without measuring the mass of the object or/and the acceleration) or what am I doing wrong?

P.S English isn't my first language! :)

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# Homework Help: Kinetic friction

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