Question

which unit is measure by loundnes ?​

Answer 1

Answer:

One sone is arbitrarily set equal to the loudness of a 1,000-hertz tone at a sound level of 40 decibels above the standard reference level (i.e., the minimum audible threshold). A sound with a loudness of four sones is one that listeners perceive to be four times as loud as the reference sound.

Answer 2

Answer:

vibration is measured bu loudness

so the answer is vibration