How do we hear the sound of the sea in a seashell?

When you hold a seashell up to your ear, you hear the quiet roar of waves crashing on a distant beach. This is because any air that makes its way into the shell's cavity gets bounced around by its hard, curved inner surfaces, in a process known as reverberation. The processes of reverberation and (acoustic) amplification within the cavity of the shell produce this sound we hear and attribute many legends to.

 Putting it simply, the resonating air inside the shell produces the sound.

Question by: Aadithyarajan B