Answer:
Fields and variables are proportional
Explanation:
To solve the problem we must first identify the Vector Intensity,
The intensity is given by:
![I = I_ {0} cos^2 (\theta)](https://tex.z-dn.net/?f=I%20%3D%20I_%20%7B0%7D%20cos%5E2%20%28%5Ctheta%29)
We also know that the change given by the Intensity is always the square of the amplitude,
This is,
![I = A ^ 2](https://tex.z-dn.net/?f=I%20%3D%20A%20%5E%202)
The intensity is <em>proportional</em> to the change exerted on ![cos ^ 2 (\theta)](https://tex.z-dn.net/?f=cos%20%5E%202%20%28%5Ctheta%29)
That is to say that in turn the amplitus is <em>proportional</em> to the Intensity.
On the other hand, relating the two variables we have
![A ^ 2 = A ^ 2_ {0} cos ^ 2 \theta](https://tex.z-dn.net/?f=A%20%5E%202%20%3D%20A%20%5E%202_%20%7B0%7D%20cos%20%5E%202%20%5Ctheta)
![A = A_ {0} cos \theta](https://tex.z-dn.net/?f=A%20%3D%20A_%20%7B0%7D%20cos%20%5Ctheta)
In this way we can conclude that the electric field of intensity is also <em>proportional</em> to ![cos ^ 2 \theta](https://tex.z-dn.net/?f=cos%20%5E%202%20%5Ctheta)