![]() ![]() What is the intensity of the light transmitted by the second polarizer?Īpplying Malus' law, the intensity after going through the second polarizer is: (b) The light now passes through a second polarizer, which has its transmission axis rotated by 30 degrees relative to the axis of the first polarizer. Therefore, the transmitted intensity is 500 W / m 2. When unpolarized light passes through a polarizer, the intensity is cut in half. What is the intensity of the light transmitted by the first polarizer? (a) Unpolarized light, with an intensity of 1000 W/m 2 is incident on the first polarizer. This problem deals with light passing through a succession of polarizers as indicated in the sketch: The easiest one to use here is the motional emf equation: Now we can apply an induced emf equation. ![]() (c) What is the value of the constant velocity v of the loop? Fortunately, it's easy because we know both the current and resistance in the loop, so we can apply the familiar equation from circuits: (b) What is the induced emf that is generated in the loop and causes the current I to flow?Īlthough this is an induced emf problem, there isn't enough information here to solve for the induced emf using an induced emf equation. The first picture, with current counter-clockwise, is correct. Current flowing counter-clockwise around the loop generates a magentic field out of the page (the right-hand rule can be used to determine this - if you curl your fingers on your right hand in the direction of the current, your thumb points in the direction of the field produced by that current). Lenz's law says that if the magnetic flux through the loop is increasing into the page, the loop will set up a flux out of the page to try to cancel the change. The loop is moving into the field, which points into the page. ![]() (a) Which way will the induced current flow in the loop? An induced current of I = 0.043 amperes is flowing around the loop. The magnetic field is perpendicular to the plane of the loop and into the page as shown in the sketch. A square loop of wire with sides of length L = 0.17 m and total resistance R = 50 ohms is moving with constant velocity v into a region of constant magnetic field B = 0.76 T. One final note: to rotate light from one polarization direction to another you reduce the loss of intensity by using more polarizers.1. After emerging from the first polarizer the intensity is 16 * 3/4 = 12 W/m 2, and is reduced to 12 * 3/4 = 9 W/m 2 after going through the second. Going through each polarizer the intensity is reduced by a factor of 3/4. What is the intensity of the light emerging from the second polarizer now? What is the intensity of the light emerging from the first polarizer now? The polarization direction of the incident light is 20 o from the vertical. Now a linearly polarized beam of light, with an intensity of 16 W/m 2, is incident on the same pair of polarizers. The angle between this and the transmission axis of the second polarizer is 30 o. When it emerges from the first polarizer the light is linearly polarized at 50 o. What is the intensity of the light when it emerges from the second polarizer? The light is unpolarized, so I 1 = 1/2 I o = 8 W/m 2. What is the intensity of the light when it emerges from the first polarizer? The second polarizer has its transmission axis aligned at 20 o from the vertical. The first polarizer has its transmission axis aligned at 50 o from the vertical. Unpolarized light with an intensity of I o = 16 W/m 2 is incident on a pair of polarizers. Where q is the angle between the polarization direction of the light and the transmission axis of the polarizer.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |