Decibel
Decibel (symbolo dB) est pars decima unitatis relativae Bel, quo exprimitur ratio logarithmus decimalis inter potentias quantitates duas. Adhibetur in telecommunicatione, electronica, acustica, oecologia. Valorem dB vel quantitatem relativam (per exemplum +1 dB seu -1 dB), ita mutationem indicantem, vel absolute adhiberi licet. Ratio quantitatis logarithsmo radice dix quarere potest, in formula: L P = 1 2 ln ( P P 0 ) Np = 10 log 10 ( P P 0 ) dB {\displaystyle L_{P}={\frac {1}{2}}\ln \!\left({\frac {P}{P_{0}}}\right)\,{\text{Np}}=10\log _{10}\!\left({\frac {P}{P_{0}}}\right)\,{\text{dB}}}