Another energy conservation problem

AI Thread Summary
The discussion revolves around solving an energy conservation problem, specifically problem number 8, which includes a visual aid linked in the post. The user expresses confusion about how to approach the problem, particularly in applying the principles of potential energy (PE) and kinetic energy (KE). They outline their understanding of energy conservation, stating that initial potential energy equals the sum of final potential and kinetic energy. However, they struggle with the algebraic manipulation needed to find the final velocity and mention a lack of angles in the equations provided. The conversation highlights the challenges faced in applying theoretical concepts to practical problems in physics.
vu10758
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This problem has a picture with it so I posted at

http://viewmorepics.myspace.com/index.cfm?fuseaction=viewImage&friendID=21023924&imageID=1304590013

The problem is problem number 8. How do I approach it? I have no idea what to do.
 
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vu10758 said:
This problem has a picture with it so I posted at

http://viewmorepics.myspace.com/index.cfm?fuseaction=viewImage&friendID=21023924&imageID=1304590013

The problem is problem number 8. How do I approach it? I have no idea what to do.

I believe I'm right in my method here, although I didn't do to well in kinematics:

PE=mgh
KE= 1/2mv^2

At the start you only have PE since velocity=0. When you fly off you have both PE and KE

So due the conservation of energy we have:

PE(i)+KE(i)=PE(f)+KE(f)

Furthermore:

PE(i)=PE(f)+KE(f)

h = r

mgr=mgr+1/2mv^2

Do the algebra to get the final velocity (Things cancel, you get a number). That should get you started. If I'm wrong, well maybe you can get an idea from what I posted here.
 
I don't know. I am suppose to solve for the angle, but there are no angles in the equations you gave me.

mgr-mgr = (1/2)mv^2
0 = (1/2)mv^2

which is not true
 
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