Why is the kinetic energy formula for this problem using the radius?

AI Thread Summary
The discussion centers on a problem involving kinetic energy calculations where the radius plays a crucial role in the formula. The equation presented includes terms that account for different masses and velocities, specifically incorporating the radius in the form of 12/18. The user expresses confusion about the necessity of including the radius in the kinetic energy terms. The inquiry seeks clarification on the rationale behind this aspect of the problem. Understanding the relationship between radius and kinetic energy is essential for grasping the overall solution.
pyroknife
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I attached the problem.

The solution is of the form:
.5*(5/32.2)v^2+.5(10/32.2)(12/18*v)^2 + 5*18/12*sin(60)-10*12/12*sin60=0

I don't understand why they put the radius in the kinetic energies like the 12/18 part. I know you have to do that, but I don't understand why.
 

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Hey Pyroknife,

Please submit your approach to the solution first.
 

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