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Martin
Martin, Engineer
Category: General
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Experience:  i'm 41 and i never stopped studying and experimenting
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Unpolarized light with intensity 420 passes first through

Resolved Question:

Unpolarized light with intensity 420 passes first through a polarizing filter with its axis vertical, then through a polarizing filter with its axis 23 from vertical. What light intensity emerges from the second filter?
Submitted: 4 years ago.
Category: General
Expert:  Martin replied 4 years ago.
HelloCustomer welcome to Just Answer.



This is known as the Malus law and i will assume perfect polarizer here. The unpolarized light intensity will divide by 2 after the first filter.



After, I = I0 cos^2 teta



I = Intensity after passing the second filter



I0= Intensity between the 2 filter



Teta= angle between the light polarization before the second filter compared to the polarization angle of the second filter.



So, the intensity at the end is 210 cos^2 (23) = 118.



If you replace the angle by 0, you are parallel, so it will give 210 (no attenuation). If you use 90, it will give 0, (complete attenuation).

Martin, Engineer
Category: General
Satisfied Customers: 4072
Experience: i'm 41 and i never stopped studying and experimenting
Martin and 111 other General Specialists are ready to help you
Customer: replied 4 years ago.
Dude your awesome. Thanks
Expert:  Martin replied 4 years ago.
My pleasure. Feedback are always welcome.
Customer: replied 4 years ago.
What information do you need?
Customer: replied 4 years ago.
The answer has to be in mV.
Expert:  Martin replied 4 years ago.
None, all is fine, i just use "info request" so that customers don't click 2 times on accept. I was just mentioning that it's possible to let feedback after you accept an answer. Not an obligation, just nice when someone does.

As for the mV (millivolt?) i don't know how this apply. Light intensity unit is the candela.
Customer: replied 4 years ago.
Are you trying to answer the second question about the magnetic field.
Customer: replied 4 years ago.
The first question about the polarized light, I already recieved. So, I'm good with that answer. Do you need more info on the second question.

A 30-turn, 10-cm-diameter coil is oriented in a vertical plane with its axis aligned east-west. A magnetic field pointing to the northeast decreases from 0.82 T to 0.18 T in 2.3 s. What is the emf induced in the coil?
Expert:  Martin replied 4 years ago.
Sorry, i see, you have another separate question. I can't answer that one as it's not under the general category. I can't answer in the homework category. Someone will get to yo for this one eventually.

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