SOLUTION: When measuring the intensity of an earthquake, a seismometer is used 100km away from the core of the earthquake. The equation used to determine the magnitude is M=log(A)+3, where A

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Question 1176634: When measuring the intensity of an earthquake, a seismometer is used 100km away from the core of the earthquake. The equation used to determine the magnitude is M=log(A)+3, where A is the recorded trace amplitude (in millimetres) of the quake.
a) Find the magnitude of an earthquake that records a trace amplitude of 1.5mm.
b) Find the magnitude of an earthquake that has an amplitude of 10 times the amplitude in part (a).

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
a. M=log (1.5)+3
=3.18
b.M=log(15)+3
=4.18, which it should be, since a change in magnitude of 1 is 10 x as strong.