The 1989 World Series San Francisco quake was initially repo

The 1989 World Series San Francisco quake was initially reported to have magnitude 7.0, but later this was revised to 7.1. How much energy released corresponds to this increase in magnitude

In 2009, the minimum wage in California was $8.00. If we assume the growth of this minimum wage is exponential and is growing at the rate of 2%, then the length of time until the minimum wage reaches d dollars is modeled by the formula

t = 50 ln (d/8)

In what year would you expect the minimum wage to be $10.00

Solution

Formula for Richter Scale : M= (logE -11.8)/1.5

E ----> energy

So,

E = 10^(1.5M +11.8)

So, E1 = 10^(1.5*7 +1.8 ) =10^12.3

E2 = 10^(1.5*7.1 +1.8 ) =10^12.45

E2/E1 =10^0.15 = 1.41

So, with rincrease in magnitude it measn 1.41 times more energy

then the length of time until the minimum wage reaches d dollars is modeled by the formula

t = 50 ln (d/8)

minimum wage = $10.0 ; find t ?

t = 50ln(10/8) = 11.16

2009 +12 = 2021

In the year 2021 we expect min. wage to be$10.0