The problem states that: "Bruce stands on a bank beside a pond, grasps the end of a 10.0m long rope attached to a nearby tree and swings out to drop into the water. If the rope starts at an angle of 35 degrees with the vertical, what is Bruce's speed at the bottom of the swing?(adsbygoogle = window.adsbygoogle || []).push({});

Variables:

angle of the rope with the vertical: 35 degrees

Length of rope: 10m

I'm trying to use the equation for the change in gravitational potential energy, where the Work due to gravity = -mg(yf-yi) which is equal to Kf-Ki, and therefore -mg(yf-yi)= -1/2mvi^2+-1/2mvf^2. With the initial velocity as 0 and the masses canceling out the solution should be Vf=[tex]\sqrt{}[/tex]2g(yf-yi).

I am apparently either setting up the question wrong, or going about it wrong all together. I'm pretty much stumped as to what I'm doing wrong and how to fix it. If someone could point me in the right direction I'd be ecstatic...

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# Homework Help: Gravitational Potential Energy of a rope

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