B Potential energy in standing wave compared to traveling wave

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In the discussion on potential energy in standing versus traveling waves, it is noted that elements of a traveling wave at maximum displacement have zero instantaneous velocity and minimum tension, resulting in lower energy compared to other string elements. However, a sinusoidally contoured string, which is longer than a straight string, possesses greater elastic potential energy. The relationship between kinetic and potential energy in standing waves is highlighted, where maximum displacement leads to zero kinetic energy. At nodes, both kinetic and potential energy equal zero, while at antinodes, potential energy reaches its maximum. This analysis illustrates the energy dynamics in both wave types.
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Why is the potential energy of a standing wave maximum when the displacement is maximum, but for a traveling wave, it is when the displacement is zero?
From hyperphysics, "The unique point in the case of the traveling wave in the string is the element of the string that is at the maximum displacement as the wave passes. That element has a zero instantaneous velocity perpendicular to the straight string configuration, and as the wave goes "over the hump", it also has minimum tension. So that element of the string has the minimum energy compared to other elements along the sinusoidal contour. This does not imply that a wavelength of the sinusoidally contoured string has less potential energy than the straight string. The sinusoidally contoured string is longer than a wavelength of straight string and will have greater elastic potential energy. As that sinusoidal contour moves along the string, it transports energy. "

Doesn't this also apply to a standing wave since it is a superposition of two traveling waves?
 
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I think for standing waves
kinetic energy + potential energy = f(x) a function depending on the position.
It means when displacement is maximum kinetic energy is zero.
At nodes kinetic energy = potential energy = f(x) = 0. At antinodes f(x) has maximum value.
 
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