Find the magnitude of an earthquake with intensity 52,000,000I0.

Question

The Richter scale magnitude Rof an earthquake of intensity Iis defined as R=log(II0),where I0is a small threshold intensity. Find the magnitude of an earthquake with intensity 52,000,000I0.

Answer 1

R = log(52,000,000) = 7.716  or  

   = log(5.2x10⁷⁾

   = log(5.2) + log(10⁷⁾

   = 0.716 + 7

   = 7.716