Trouble with Conservation of Energy And Friction

AI Thread Summary
The discussion revolves around the conservation of energy in the context of a hockey puck sliding on ice and coming to a stop due to friction. The initial energy of the puck is calculated using the formula Ei = 0.5mv0², while the energy lost to heat is expressed as Eth = μk * n * Δx. The user attempts to relate these energies by determining the distance the puck travels before stopping, leading to confusion when the mass (m) seemingly disappears from the equations. Ultimately, the user realizes their mistake in the calculations but expresses frustration over the process. The conversation highlights common challenges in applying energy conservation principles in physics problems involving friction.
MrBillyShears
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Ok, I'm driving myself mad, so if someone could settle this for me, that would be helpful. So, I'm imagining something like a hockey puck going across ice and coming to a stop. I'm trying to account for the initial energy, Ei, and the final energy, Ef. So this hockey puck starts with a velocity, v0, a mass, m, and of course under the influence of gravity, g. So, its Ei is.5mv02. Now, to account for the heat released, you use Eth=μk∫ndx, (n is the normal force). Now, since n is constant in this case, it reduces to Eth=μknΔx. Now we find Δx by finding the time it takes for the puck to come to rest, at+v0=0, -μkgt+v0=0, then we put that time in for the formula, .5at2+v0t=Δx. Then, we set Ei equal to Eth, but I get .5mv02=.5v02, so, what happened to the m? Why am I not getting equal things?
 
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Never mind, my mistake. Don't know how to delete it.
 

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