### Home > A2C > Chapter 11 > Lesson 11.3.2 > Problem 11-150

11-150.

Logarithms are used to measure the “loudness” of sound. Decibels (dB) are logarithmic units used to descrbe a ratio of two levels of intensity or pressure. The difference between two levels of sound pressure (*P*_{1} and *P*_{2}) is defined as * _{\large{10 \operatorname { log } ( \frac { P _ { 1 } } { P _ { 2 } } )}}*dB. Usually, when decibels are used to describe just one sound, it is assumed that that sound is being compared to a reference level of 20 micropascals.

How many decibels correspond to doubling the pressure of a sound?

What is the sound pressure of a sound described as 60 dB?

What does 0 decibels mean?

The sound ratio is

. How many times more pressure is in a sound of

than of ? times more pressure.