Answer:
Intensity of beam 18 feet below the surface is about 0.02%
Explanation:
Using Lambert's law
Let dI / dt = kI, where k is a proportionality constant, I is intensity of incident light and t is thickness of the medium
then dI / I = kdt
taking log,
ln(I) = kt + ln C
I = Ce^kt
t=0=>I=I(0)=>C=I(0)
I = I(0)e^kt
t=3 & I=0.25I(0)=>0.25=e^3k
k = ln(0.25)/3
k = -1.386/3
k = -0.4621
I = I(0)e^(-0.4621t)
I(18) = I(0)e^(-0.4621*18)
I(18) = 0.00024413I(0)
Intensity of beam 18 feet below the surface is about 0.2%
Answer:
= 3.869 × 10^-6 J/m³
Explanation:
Intensity is given as W/m^2 which is equivalent to J/ (s*m^2)
Speed of light is 2.99792 × 10^8 m/s.
Therefore;
Electromagnetic energy per cubic meter = Intensity/speed of light
= 1160 J/ (s*m³)/ 2.99792 × 10^8 m/s.
<u>= 3.869 × 10^-6 J/m³</u>
There are many things in this feeble world that our species are incapable of comprehending such as what lies beyond our galaxy
what is the meaning of life
and most importantly why doesnt my dad love me
I believe that the answer to the question asked above is the following
sound intensity = sound power / (4 pi R2<span>)
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so if you decrease the intensity by a factor of 2 the sound wave will also decrease by a factor of 2.
Hope my answer would be a great help for you. If you have more questions feel free to ask here at Brainly.