Physics

Three polarizers are placed in succession with their axes of polarization as follows: P1 vertical, P2 at angle theta to the vertical, and P3 at 90 degrees to the vertical. Unpolarized light of intensity I.0 is incident on the first polarizer. The final intensity after the passing through the 3 polarizers is measured to be (3/32)I.0
Determine the angle theta between the first polarizer P1 and second polarizer P2.

  1. 👍 0
  2. 👎 0
  3. 👁 223
  1. When unpolarized light passes through a polarizer, the intensity is reduced by a factor of ½. ... When polarized light of intensity I0 is incident on a polarizer, the transmitted intensity is given by I = I0cos2θ, where θ is the angle between the polarization direction of the incident light and the axis of the filter.
    because each polarizer allows 1/2 cos^2Theta where theta is some angle from the vertical. So if Theta for P1 is zero, then
    Itrans=1/2 Io
    Then, the light getting thru P2 is.5Iocos^2Theta, and finally, the light getting thru the final P3 is .5 Io (cos^2Theta *cos^2(90-Theta)
    If Io is 1.0, then
    .5(cosTheta*sin(90-Theta)=3/32
    cosTheta * (sin90sinTheta-cos90sinTheta)=6/32
    but cos90=0 so
    sinTheta*cosTheta=1/2 sin 2*theta=6/32
    sin Theta= sqrt (12/32)=.612
    Theta=37 deg

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics

    please check these for me: If atmospheric refraction did not occur, how would the apparent time of sunrise and sunset be changed? a. both would be later b. both would be earlier c. sunrise would be later, and sunset would be

    asked by physics on March 12, 2009
  2. Science

    2.Why are biologists concerned about ecosystem disruption? 1.Explain the process of succession. Succession is a natural change in the area that results in one group of plants replacing a group before. for #1 that is all I have so

    asked by Katherine P on March 11, 2016
  3. Physics

    A ball is thrown horizontally from the roof of a building 9.0 m tall and lands 8.5 m from the base. What was the ball's intial speed? I have no idea how to do this problemm or what formulas to use because of the fact that I do not

    asked by Physics on July 5, 2009
  4. Physics

    Two identical rollers are mounted with their axes parallel, in a horizontal plane, a distance 2d = 40.4 cm apart. The two rollers are rotating inwardly at the top with the same angular speed. A long uniform board is laid across

    asked by Jennie on January 4, 2012
  5. biology

    i need a short story about a ecosystem that is disturbed and undergoes succession

    asked by shelby on May 17, 2011
  1. Science

    What is the main difference between primary and secondary succession? A.) The climax of primary succession is a pine forest. B.) Primary succession begins with bare rock. C.) Secondary succession begins ith mosses and linches.

    asked by Man with a actual huge screw is his head on October 21, 2019
  2. engineering mechanics

    The resultant if a certain system of forces has x and y components. Determine the components of this resultant with respect to N and T axes rotation 30 degree counterclockwise relative to the x and y axes. Ans. Rn= 500 lb Rt= 266

    asked by shan on May 2, 2015
  3. algebra

    Find the coordinates of the points of intersection of the graph of y=13−x with the axes and compute the area of the right triangle formed by this line and coordinate axes. can u guys plz find answer + explain this problem is

    asked by allie on October 12, 2016
  4. MAJOR HELP NEEDED

    So this is what I have to do and I really don't get it. I've gotta describe ecological succession in terms of changes in the abiotic parts of an ecosystem. What do I do? Ecological succession refers to the changes that take place

    asked by Andrea on July 7, 2010
  5. URGENT Physics help

    Positively charged Object A is brought close to neutral Object B but does not touch it. The two objects begin to attract each other. What is this process called? (Points : 1) grounding charge polarization conduction repulsion 4.

    asked by Hannah on April 21, 2014
  6. psychology

    please explain group polarization

    asked by andrew on October 7, 2018

You can view more similar questions or ask a new question.