Another energy conservation problem

[vu10758]

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.

 

[mkienbau]

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.

 

[vu10758]

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