Question 57019
What relevance and application of logarithmic functions in real-life situations
: 
One is the measurement of sound and RF signal strength. The ear itself appears to logrithmic. The measuring of sound of music, noise etc. is measured in decibels:

A decibel (DB)  = 10*(logP1/logP2) measures the ratio of Power (P1) to Power(P2), if it is referenced to 1 milliwatt, it is referred to as DBM. A whole set of formulas for power/voltage/impedance uses the logrithmic relationships.