(I know this type of problem has been discussed on here before, but I still don't understand what to do next)(adsbygoogle = window.adsbygoogle || []).push({});

The attached drawing shows a large cube (mass=55kg) being accelerated across a horizontal frictionless surface by a horizontal force P. A small cube (mass=4.5kg) is in contact with the front surface of the large cube and will slide down unless P is sufficiently large. The coefficient of static friction between the cubes is 0.55. What is the smallest magnitude that P can have in order to keep the small cube from sliding downward?

So far I have found that:

Normal force=ma, (4.5 x 9.81)= 44.1 N

F sub s=Mu sub s times mg, (.55 x 44.1)=22.05N

I've also attatched a diagram of all the forces acting on the small cube, and concluded that an additional force of 22.05N is necessary to keep the small cube on the large one. I just don't know where to go from here to find P.

Thanks for your help.

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# Homework Help: Small cube/large cube sliding problem with friction please help quickly :/

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