What exactly determines the energy of a wave? the intensity? or the frequency?

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The energy of a wave is influenced by both its frequency and amplitude, depending on the type of wave. For mechanical waves, such as sound waves, the amplitude is the key factor that determines energy, as higher amplitudes carry more energy. In contrast, for electromagnetic waves like photons, energy is determined by frequency. The discussion highlights that in stationary waves, although amplitudes may cancel, the wave can still propagate due to the energy carried by other factors. Overall, the relationship between wave energy, intensity, and frequency varies based on the wave's nature.
mutineer123
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I am taking AS level Physics rite now, and wanted to know what exactly determines the energy of a wave. Well since I have recently learn of stationary waves(sound waves) being standing. I know that they are formed by the superimposition of the reflected waves on the incident waves. This causes the amplitude to cancel out, and become zero. So intuitively I guess the frequency decides a waves energy, because if intensity did, then in a stationary wave, the amplitudes canceling out would make the intensity nil as well(I=κA6^2), so this will make the sound stop, which it clearly does not.
So is this reasoning right?
 
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It depends on the context actually. In terms of mechanical waves, for example a water wave ripple in a pond, more energy is carried by the wave for high amplitudes. Photons are another type of wave, but they carry energy in their frequency. A sound wave is a mechanical wave, and so the amplitude determines the energy of the wave.
 
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