Sharp EL-W516T

19
Operation Display
logE = 4.8 + 1.5M
logE - 4.8
1.5
M =
(1)
(2)
1.5 1
1.5 2
If E (units: joules) is the amount of energy released by an
earthquake and M is the magnitude, the relation
holds.
If E' is the energy when the magnitude increases by N,
holds.
(1) When the magnitude increases by 1, by what factor does
the energy increase?
(2) When the magnitude increases by 2, by what factor does
the energy increase?
(3) The amount of energy in 20,000 tons of TNT is 8 x 10
13
joules.
When this energy is converted to a magnitude,
holds. Find the magnitude M.
= 10
1.5N
E'
E
Exponential, Logarithmic
<Example 1>
(3)
4.8
8
13
1.5