Question

An earthquake is California measured 4.9 on the Richter scale. Use the formula R=log(A/Ao) to determine approximately how many times stronger the wave amplitude A of the earthquake was than Ao

Answer 1

we have that the formula for earthquakes is given by

$R=\log (\frac{A}{A_0})$

In our case R=4.9, hence,

$\log (\frac{A}{A_0})=4.9$

since we must find the ratio A/Ao:

$\frac{A}{Ao}=e^{4.9}$

or

$\frac{A}{Ao}=134.29$

by rounding down, we have

$A=134\cdot A_0$

this means that, A is aproximately 134 times more stronger than Ao.