Why We Hear The Ocean In Seashells

Sorry to break it to you, but it's not actually the ocean we hear when we put a seashell close to the ear. It would be really nice if it was the case.

What we hear is the ambient noise around us. The shape of the seashell acts like a resonator and different frequencies are augmented. The size and shape of the seashell determine the actual sound we perceive. Any cone-shaped object can be used to demonstrate this phenomenon, such as an empty cup or by cupping your hands over your ears.
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