How Much Work Does Friction Do on a Skateboarder Descending a Ramp?

AI Thread Summary
To determine the work done by friction on a skateboarder descending a ramp, the conservation of energy principle can be applied. The initial kinetic energy (K[i]), initial potential energy (U[i]), and work done by nonconservative forces (W[nonconservative]) must equal the final kinetic energy (K[f]) and final potential energy (U[f]). The problem involves calculating the forces and distances involved, particularly focusing on the frictional force. The discussion also hints at the relevance of angular velocity but does not provide a clear resolution. Understanding these concepts is essential for solving the problem effectively.
Jtappan
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Homework Statement



Jim rides his skateboard down a ramp that is in the shape of a quarter circle with a radius of 6.50 m. At the bottom of the ramp, Jim is moving at 2.82 m/s. Jim and his skateboard have a mass of 67.0 kg. How much work is done by friction as the skateboard goes down the ramp?
__________ J



Homework Equations



w=f*d

The Attempt at a Solution



Is this sort of a angular velocity problem? I don't even know how to set this one up
 
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disregard this post...sorry i posted it twice
 
You could try conservation of energy:

K + U + W[nonconservative forces] = K[f] + U[f]

Where the work done by nonconservative forces is the force of friction times the distance.
 
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