On Richter scale, magnitude M of an earthquake of intesity I is:
M = (ln(I)) - ln(I)0)/(ln(10))
Where I0 is the min intensity used for comparison, and assume that it equals 1.
a. Find intensity of 106 San Fran earthquake (M = 8.3)
This is what I did:
I plugged in the givens.
8.3 = (ln I - ln(1))/ln(10)
I know that ln(1) = 0 so that gets taken out
I get left with:
8.3 = (ln I)/(ln 10)
Not sure if I did this correctly... But I multiplied both sides by ln 10.
But then I got lost when there was another ln on the other side.
I think I forgot something that was crucial in order to find the variable of something with a natural log.
Can someone remind me or help me out?
I think this is what they did:
I converted the last thing I did into exponential (the part where I multiplied both sides by 10)
I=eln10*8.3... Oh wait I just figured it out, it equals the answer, but it doesn't look like the 108.3 thing xD. But yeah, if anyone wants to explain to me how
eln10*8.3 = 108.3 that would be nice
b. Find factor by which intensity is increased if Richter scale measurement is doubled
I'm not really sure what to first do.
The answer is: 10R
So I'm assuming it was the base to the power of R?
Is it really just like that, or was there more steps before it?