Formula for I vs. m
With mathematics which we won’t derive here, you
can show this is equivalent to the equation:
This
second equation is easy to use on a calculator.
If you remember that log( 10n ) = n, for example
log( 104) = 4, log (105) = 5, log(106) = 6,
you can use it even without a calculator.
If you remember that log( 10n ) = n, for example
log( 104) = 4, log (105) = 5, log(106) = 6,
you can use it even without a calculator.
Intensity
Ratio
Magnitude Difference
10,000,000,000
25
...
...
1,000,000
15
...
...
10,000
10
4,000
9
1,600
8
630
7
250
6
100
5
40
4
16
3
6.3
2
2.5
1
1
0