PHYSICS HELP please!!!!!?

[Adam B]

Please help me with this worksheet!!! it's soooo hard!!! AHHHHHHHH!!!! if you can help me, here's the link (also click on "all sizes" in the bar above the picture to make it larger)...Thank yoooooouuuu...I WILL REWARD WITH POINTS...oh yea : ) the link:

http://www.flickr.com/photos/24568838@N04/2324359463/

[odu83]

a) Using energy
M*g*(H-2*R)=.5*M*v^2
v=sqrt(2*g*H)
8.16 m/s

b)
the centripetal acceleration is v^2/R

to find v^2, use energy
M*g*H=.5*M*v^2
g*4*R=v^2

so the force is
M*g*4
19.6 N

c)
using energy
M*g*(4*R-R)=.5*M*v^2
solve for v

v=sqrt(2*g*3*R)
7.07 m/s

d) Only the reaction to the centripetal
M*v^2/R
29.4 N

e)
Conservation of momentum. The speed is the same as point B
8.16 m/s
M*8.16=3*M*v
solve for v
v=2.72

f)
3*M*g*h=.5*3*M*2.72^2
h=.5*2.72^2/9.8
h=0.37747 m

g)
cos?=(3*R-h)/(3*R)
31.57 degrees
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