A small cube of mass m is placed on the inside of a funnel rotating about a vertical axis at a constant rate of w revolutions per second. The wall of the funnel makes an angle theta with the horizontal. The coefficient of static friction between cube and funnel is u and the center of the cube is at a distance r from the axis of rotation. Find the (a) largest and (b) smallest values of w for which the cube will not move with respect to the funnel.(adsbygoogle = window.adsbygoogle || []).push({});

I of course try to draw a free body diagram that looks pretty weird.

does w_min look like sqrt(g(sin(theta)-ucos(theta))/r(cos(theta)+usin(theta)))? And wmax the same except for the fact that you add ucos)theta_ on the top except for subtracting.

The problem is also Halliday volume 1 chapter 5 problem 18

Thanks!

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# Homework Help: Friction + centripetal acceleration problem

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