Question

How is loudness related to the amplitude of wave ?

Answer 1

Higher amplitude have high loudness and vice versa. In other words, loudness is directly proportional to the amplitude.
Hope it helps u.

Answer 2

Hey there!

Relation between Loudness and Amplitude:

Loudness is directly proportional to square of the amplitude.

i.e Loudness ∝ (Amplitude)²

Example:

When a body vibrates with a greater amplitude, it sends forth a greater amount of energy and hence the energy received by the eardrum is large, so the sound appears louder.

Hope It Helps You!