Hello there, this is my first posting on this board. I am a third year physics major and I've taken a lot of courses but I've always just scraped by with a large amount of help from small groups. I'm thinking about reconsidering my major because I feel like I no longer can understand the concepts.. but anyways, I came across this problem and I am stumped.(adsbygoogle = window.adsbygoogle || []).push({});

Using {r, phi, z} coordinates write the equation of motion for a small block that is free to move on the inside surface of an upper cone under the influence of gravity. Repeat this problem with the addition of simple friction.

I have done the free body diagram but I don't know how to post that on here. Anways this is what i got:

r^=-Ncos(phi)=-mv^2/r

z^=Nsin(phi)-mg=0

Then divide z^ by r^ and get this:

tan(phi)=rg/(v^2)

???

I really have no idea what I am doing. Any help or sense of direction would be greatly appreciated.

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# Homework Help: Block sliding on the inside of a cone

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