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Sunday, October 24, 2010
Ch9 3 #1
Remember that total energy is conserved, and figure out when either KE or PE is zero. When KE is zero PE must be its maximum and vice versa
5 comments:
Anonymous
said...
For part G, the KE is 1/2mv^2 and the PE is 1/2kx^2 correct?
5 comments:
For part G, the KE is 1/2mv^2 and the PE is 1/2kx^2 correct?
How do I relate them in terms of k and A?
Remember that A is the Amplitude.
And in this case The Amplitutde A = A/2
I tried 1/2*k*A/2
But The annoying thing is I don't know if this is wrong or if I'm just inputing the data in a wrong way.
The total energy of the system never changes, and for the point labeled "A", E_TOT = KE + PE = 0 + (1/2)kA^2, so from this E_TOT = (1/2)kA^2.
At "B", x = A/2 (as the previous post said. Then
KE(B) = E_TOT - PE(B)
and you can figure out PE(B) knowing that x = A/2.
thank you
I still can't figure g out? 1/2*k*A^2 + 1/2*k*A/2 is wrong ... this is too confusing!
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