Question

Define magnitude of an earthquake.

Answer 1

The Richter scale, developed in the 1930s, is a base-10 logarithmic scale in order to cover the huge range of earthquakes. It defines magnitude as the logarithm of the ratio of the amplitude of the seismic waves to an arbitrary, minor amplitude, as recorded on a standardized seismograph at a standard distance.

Answer 2

Heya!!
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Magnitude is a measure of the amount of energy released during an earthquake. It may be expressed using several magnitude scales. One of these, Used in Southern California, is called the Richter scale.
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