Analysis on the circular motion

AI Thread Summary
The discussion focuses on the dynamics of a child sliding down a slide and the conditions for maintaining contact during circular motion. It emphasizes the need for centripetal force to keep the child on the slide, noting that the child will lose contact when their speed exceeds the force that can hold them in circular motion. The equation n - mg cos θ = -m(v^2/R) is highlighted as a key relationship, but participants seek clarification on how to derive the child's height from this. Energy conservation principles are suggested as a method to determine the child's speed in relation to their height. Understanding these concepts is crucial for analyzing the motion effectively.
UrbanXrisis
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Is the answer just H-R?

I don't know what they are asking. Any tips?
 
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Do you really think the child loses contact with the slide before even reaching the rounded section? :rolleyes: Don't just guess.

Consider that in maintaining contact over the rounded section, the child must undergo circular motion. And that requires a centripetal force. (What force holds the child to the slide?) At some point, the child will be going too fast for the force to maintain the circular motion---off he goes.
 
At some point on the circular section the child's speed will be such that mv^2/r exceeds the normal force holding him on the slide.
 
When the normal force = 0 the boy loses contact with the surface.

So on your analysis on the circular motion

n - mg \cos \theta = -m \frac{v^2}{R}
 
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but how does that get me the height?
 
You should be able to determine the speed of the child in terms of her height.

HINT: Energy is conserved!
 
What i said above means when v^2 = Rg \cos \theta it will be at the point it leaves the surface.

Hint: Use this fact and Tide's hints.
 
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