Polarization question from Berkeley Review

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MedGrl@2022

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Are the questions in the Berkeley Review chapters meant to be A LOT harder than what you would see on the MCAT. I have found myself struggling through some physics chapters in TBR. They seem to ask really hard questions which I sometimes do not know how to even begin solving. I sometimes find their explanations to be a little difficult too. For example,

Example 10.1B in the Lights and Optics section:

When unpolarized light reflects off of a specular (mirrored) surface at a glancing
angle with respect to the surface, the light can partially polarize parallel to the
surface. That is, the parallel polarized light is more intense than the
perpendicular polarized light. If this surface is lying on flat ground, in what
orientation should a polarizing anti-glare filter be with respect to the ground, in
order to minimize the total light intensity through the filter? The polarizer's
polarization axis should be oriented at:

A. 0 degrees with respect to the ground.
B. 45 degrees with respect to the ground.
C. 90 degrees with respect to the ground.
D. 180 degrees with respect to the ground.

According to BR, the answer is C. How does one go about answering this question? If you could include pictures that would be great.

There are two polarizers in this problem right. The mirror acts as a partial polarizer (which alters the light rays (as they are reflected) to orient parallel to the mirror to be more intense). Does the polarizer/mirror absorb as it filters the (perpendicular) light? What is the polarization axis? How am I supposed to know at which angle the polarizing anti-glare filter polarizes the light? If the anti-glare filter is at 90 degrees how does it alter the light? does the light go first through the anti-glare filter or go through the filter after being reflected from the polarizing mirror?

Do all mirrors act as partial polarizers?

Where can I learn more information on this? Will questions like this be on the MCAT or is this above and beyond the scope and what is expected from me on the MCAT?

Thank you for all your help.

Best,

Verónica

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It took me a while... but I am happy to report that I figured it out. This website is AWESOME... http://www.physicsclassroom.com/class/light/u12l1e.cfm#trans

new question... mirrors are non-metallic in this senario, right? On the MCAT am I supposed to assume that mirrors are metallic or non-metallic? According to the website, metallic surfaces do not polarize light whereas non-metallic surfaces polarize light such that light is parallel to the reflecting surface. Neither of these scenarios such affect the convex or concave mirror senarios that the MCAT tests though, right?

Thank you for all your help. :)
 
It took me a while... but I am happy to report that I figured it out. This website is AWESOME... http://www.physicsclassroom.com/class/light/u12l1e.cfm#trans

new question... mirrors are non-metallic in this senario, right? On the MCAT am I supposed to assume that mirrors are metallic or non-metallic? According to the website, metallic surfaces do not polarize light whereas non-metallic surfaces polarize light such that light is parallel to the reflecting surface. Neither of these scenarios such affect the convex or concave mirror senarios that the MCAT tests though, right?

Thank you for all your help. :)

I 2nd the awesomeness of Physics Classroom. Really helped me drill down some major concepts
 
Know couple of things.
1. Only transverse wave get polarized , not longitudinal waves
2. It is the electric field that oscillates in one direction when polarizing light.
3. Maximum amount of light emerges, when pair of polarizing filters at 0 or 180 degrees angle with each other. Eg ; 180 – theta =
4. Minimum light emerge (zero intensity) with the pair of polarizing filters at 90 degrees angle with each other.

Read it all but more on Part 4 for y your question.
 
I 2nd the awesomeness of Physics Classroom. Really helped me drill down some major concepts

I wish I had found it sooner... but alas I still have more than a month until my test date... I am sure that it may still come in use. :)
 
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