# trig word prob

• January 22nd 2006, 06:11 AM
mathAna1ys!5
trig word prob
Light travels like waves in many different planes. If light is polarized, all of the waves are traveling in parallel planes. You may havepolarized sunglasses taht eliminate glare by polarizing the light. Suppose vertically-polarized light with intensity (I) strikes a polarizing filter with its axis at an angle of theta with the vertical. The intensity of the transmitted light, (O), and theta ate realated by the equation cos theta= square root of I/O

a. If one-fourth of the polarized light is transmitted through the lens, at what angle is the lens being held?

b. At what angle will none of the polarized light be transmitted through the lens?
• January 22nd 2006, 06:53 AM
earboth
Quote:

Originally Posted by mathAna1ys!5

a. If one-fourth of the polarized light is transmitted through the lens, at what angle is the lens being held?

b. At what angle will none of the polarized light be transmitted through the lens?

To a)
If $I=\frac{1}{4} \cdot O$ than you get:

$\cos \theta = \sqrt{\frac{I}{O}} \mbox{means} \cos \theta = \sqrt{\frac{\frac{1}{4} O}{O}} =\frac{1}{2}$

and you get: $\theta = 60^\circ$

to b)

Use your equation: $\cos \theta = \sqrt{\frac{I}{O}}=0$ is only possible if $\theta=90^\circ$

Bye