Q: There is a mass of a mass A (2kg ) sitting on top of a mass of B ( 4kg), which is sitting on top of a mass of C(3 kg). The static friction between A and B is .5; and between B and C is .5 and between C and the ground is .8. Mass B is tied to the wall. What is the minium force required to pull block C out from under block B?(adsbygoogle = window.adsbygoogle || []).push({});

A: Well I am really confused about static friction, the Normal force acting on Mass C is 9kg*9.8N=88.2 N, and is u static is .8+.3=.13, so therefore the static force is

us.* Normal force = Static force =13*88.2 = 88.2N (is that force it would take to move Mass C?)

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# Homework Help: Static friction

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