# Question about the Richter Scale

FMF
Science 16 May '08 13:16
1. FMF
Main Poster
16 May '08 13:16
In the Richter scale 8.0 is ten times bigger than 7.0 . So what's the 0.1 increment? I used to think it was double: 7.8 is twice as severe as 7.7, and 7.9 is twice as severe as 7.8. But it can't be double. If you double something 10 times you get 512 times more than you started with, and if you add each of the 10 increments up, you get 1023 times more... er... Who knows how this works? If 8.0 is ten times bigger than 7.0, how much bigger is 7.1 than 7.0?
2. Palynka
Upward Spiral
16 May '08 13:421 edit
Originally posted by FMF
In the Richter scale 8.0 is ten times bigger than 7.0 . So what's the 0.1 increment? I used to think it was double: 7.8 is twice as severe as 7.7, and 7.9 is twice as severe as 7.8. But it can't be double. If you double something 10 times you get 512 times more than you started with, and if you add each of the 10 increments up, you get 1023 times more... er... ...[text shortened]... ho knows how this works? If 8.0 is ten times bigger than 7.0, how much bigger is 7.1 than 7.0?
The scale is logarithmic of base 10. This means that to get a linear scale you have to convert it, i.e. 10^8 = 10*10^7

10^7.1 = x*10^7

x=10^.1 =(approx)=1.2589 => 26% larger (approx)
3. 16 May '08 13:49
Originally posted by FMF
In the Richter scale 8.0 is ten times bigger than 7.0 . So what's the 0.1 increment? I used to think it was double: 7.8 is twice as severe as 7.7, and 7.9 is twice as severe as 7.8. But it can't be double. If you double something 10 times you get 512 times more than you started with, and if you add each of the 10 increments up, you get 1023 times more... er... ...[text shortened]... ho knows how this works? If 8.0 is ten times bigger than 7.0, how much bigger is 7.1 than 7.0?
I think 8.0 is 30 times bigger in the energy release than 7.0
4. 16 May '08 13:511 edit
Originally posted by FMF
In the Richter scale 8.0 is ten times bigger than 7.0 . So what's the 0.1 increment? I used to think it was double: 7.8 is twice as severe as 7.7, and 7.9 is twice as severe as 7.8. But it can't be double. If you double something 10 times you get 512 times more than you started with, and if you add each of the 10 increments up, you get 1023 times more... er... ...[text shortened]... ho knows how this works? If 8.0 is ten times bigger than 7.0, how much bigger is 7.1 than 7.0?
A tremor of Richter scale x magnitude is a tremor of Richter scale magnitude 1 times 10 to the power x.
So if we call the magnitude of a Richter scale 1 tremmor r then:
7.0 on the richter scale = p = r X 10 ^ 7.0
7.1 on the richter scale = q = r X 10 ^ 7.1
log (p) = 7*r
log (q)=7.1*r
log(p) / 7=log(q) / 7.1
p=10 ^ ( log(q) * 7 /7.1 )

Does that help at all?

Edit:
I think Palynka did better than me. ðŸ™‚