Sphere rolling down a ramp problem

AI Thread Summary
A solid sphere weighing 3.2 lbs rolls down a ramp with a height of 1.57 m and an angle of 18.3°. The problem involves finding the speed of the sphere's center of mass at the bottom of the ramp using conservation of energy principles. The initial equation setup for energy conservation was incorrectly formulated, leading to confusion. The correct approach involves equating gravitational potential energy to the sum of translational and rotational kinetic energy. Clarifications on the problem helped streamline the solution process.
iamtrojan3
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Homework Statement


A solid sphere of uniform density (weight = 3.2 lbs starts from rest and rolls down a ramp (H = 1.57 m, q = 18.3°.)

Find the speed of the sphere's CM when it reaches the bottom of the ramp.

haha sorry bout that...

Homework Equations



see below

The Attempt at a Solution


i dont' know what's wrong with my set up here,
m*g*d*sin(theta) = .5mv^2 + (2/5)(.5)mv^2

any help?

thanks!
 
Last edited:
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It might help if we knew what the question was!
 
Ops... forgot to add the question. silly me >.<
 
Your conservation of energy equation looks wonky. If I'm doing this right, you should have that m*g*h = (0.5)mv2 + (2/5)*(0.5)mv2. You're already given the height of the ramp!
 
i hate when they put extra information in it, you just feel obligated to use it.

yes your right, thanks a lot for the help!
 
You're welcome! :)
 
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