Question

what is (dB) in physics
like, we can't hear more than 120 dB because it is harmful for our body

Answer 1

${\large{\boxed{\textsf{\textbf{✒~~~Description :}}}}}$

In physics, $ \sf \red{decibel~ (dB)}$ is a unit used to express the $ \sf \green{ratio~ of ~two~ values}$ of a physical quantity.