How many kilowatt-hours of energy would an earthquake have to release in order to be an 8.5 on the Richter scale?

Question

The Richter scale is used for magnitude of an earthquake.  The Richter magnitude is given by R=0.67log(0.37E)+1.46 where E is he energy in kilowatt hours released by the earthquake.  How many kilowatt hours of energy would an earth quake have to release in order to be an 8.5 on the Richter sale?

Answer 1

R = 0.67*log(0.37E) + 1.46

 

8.5 = 0.67*log(0.37E) + 1.46

 

7.04 = 0.67*log(0.37E)

 

7.04/0.67 = log(0.37E)

 

10.51 = log(0.37E)

 

10^10.51 = 0.37E

 

Solve for E.