- #1
Amith2006
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- 2
Homework Statement
1) At a given point in space, the total light wave is composed of 3 phasors P1 = a, P2 = (a/2)e^(i(theta)), P3 = (a/2)e^(-i(theta)). What is the intensity of light at this point?
Homework Equations
The Attempt at a Solution
I solved it in the following way:
P = P1 + P2 + P3
= a + (a/2)e^(i(theta)) + (a/2)e^(-i(theta))
= a + (a/2)[cos(theta) + isin(theta) + cos(theta) - isin(theta)]
= a + acos(theta)
= 2acos^2(theta/2)
I = P^2
= 4a^2cos^4(theta/2)
But if P3 = ae^(-i(theta)) then this method won’t work, isn’t it? So could someone suggest a more general way to solve such problems?