The richter scale measures the intensity of earthquakes on a logarithmic scale. the magnitude of an earthquake on the richter scale can be defined by m=2/3log(e)-3.2, where e is the energy of the quake in joules. the 2011 tohoku earthquake in japan measured 9.1 on the richter scale. the 1999 hector mine earthquake in eastern california had a magnitude of 7.1. calculate the energy released by each earthquake.

Japan :

California :

Step-by-step explanation:

The magnitude of an earthquake on the Richter scale can be defined by

where E is the energy of the quake in joules.

Add 3.2 on both sides.

Multiply both sides by 3/2.

          .... (1)

It is given that the 2011 Tohoku earthquake in Japan measured 9.1 on the Richter scale.

Substitute M=9.1 in equation (1).

Therefore, the energy released by earthquake in japan is .

It is given that the 1999 Hector Mine earthquake in eastern California had a magnitude of 7.1.

Substitute M=7.1 in equation (1).

Therefore, the energy released by earthquake in California is .

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step-by-step explanation: