Question

Determine magnitude of earthquake half as intense as an 8.0 magnitude earthquake?

Answer 1

Please! I have a math midterm tomorrow (:

Answer 2

Sorry, I'm googling around for the Richter formula. I know it's a logarithmic function, but I don't remember exactly what it is. Do you have it handy?

Answer 3

This is all I have:
A = Ao x 10^R

Answer 4

Or:
M= logA / Ao

Answer 5

Try log((10^8)/2) ?

Answer 6

That seems about right. 7.69897

Answer 7

intensity=function of magnitude
whats the formula

Answer 8

or mag=Function of (intensity)
you need formula of that

Answer 9

Thanks guys!! Tom Hue you're a lifesaver! I'm pretty sure that's it too

Answer 10

Yup. 8.0 is ten times more powerful than 7.0, so somewhere in between is about right. I think the whole A0 thing is some form of distance from the epicenter where I guess 1 would be directly at it.

The formula would simply be
magnitude=log(amplitude), or 10^magnitude=amplitude.
M=8, so 10^8=A. Half that is (10^8)/2, plug it into the logarithmic, you get ~7.7.