# Logarithmic Scale

## Definition - What does Logarithmic Scale mean?

A Logarithmic Scale is a nonlinear scale which uses logarithms of physical quantities rather than the physical quantities themselves. The scales are used commonly in the light intensity, earthquake strength, pH of solutions and sound loudness. It depends upon the orders of the magnitude instead of the standard linear scale. Thus, every mark made on the scale represents the previous mark that is multiplied by some value. It is also the graphical scale present on one or both sides of the graph.

## Petropedia explains Logarithmic Scale

A Logarithmic Scale is helpful in managing data when it covers the values of large range as it can reduce the range to a more manageable range. There are two reasons for using these logs – to respond to the imbalance towards the large values and to show the multiplicative factors or the percent change. The following are the examples of Logarithmic Scales commonly used:

- The logit used for odds in statistics.
- The Richter and moment magnitude scales used for the moment in the Earth and strength of earthquakes.
- The entropy used in thermodynamics.
- The information in information theory.
- Numeric scale in pH for acidity