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4 years ago

11

Unpolarized light is passed through three successive Polaroid filters, each with its transmission axis at 45.0° to the preceding

filter. What percentage of light gets through?

1 answer:

allsm [11]4 years ago

3 0

Answer:

The percentage is $k = 12.5 \%$

Explanation:

From the question we are told that

The axis is is at $\theta = 45 ^o$

Generally the of intensity light emerging from the first polarizer is mathematically represented as

$I_{1} = \frac{I_o}{ 2}$

Where $I_o$ is the intensity of unpolarized light

Now the light emerging from the second polarizer is mathematically represented as

$I_2 = I_ 1 * cos ^2(\theta )$

$I_2 = \frac{I_o}{2} * cos ^2(45 )$

$I_2 = \frac{I_o}{2} * \frac{1}{2} = \frac{I_o}{4}$

Now the light emerging from the third polarizer is mathematically represented as

$I_3 = I_ 2 * cos ^2(\theta )$

$I_3 = \frac{I_o}{4} * cos ^2(45 )$

$I_3 = \frac{I_o}{8}$

Now the percentage of the intensity of light that emerged with respect to the intensity of the unpolarized light is

$k = \frac{\frac{I_o}{8} }{I_o } * 100$

$k = 12.5 \%$

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