Question: (a) By analogy with Problem above, argue that
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is the world's only candidate for the energy in a vibrating string.
(b) Using equations (4) and (5) above and Parseval's Theorem, show that the energy in the string considered above is finite provided that 1 and g are finite energy initial conditions.
(c) Show that the string energy is in fact constant, independent of time, and given by
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Problem: Consider the spring-mass analogue of the wave equation with X0 = XM = 0 as boundary conditions. Define the total mechanical energy
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And show (by differentiation, to cite one way) that E is independent of time.