Skip to main content
Pearson+ LogoPearson+ Logo
Ch 36: Diffraction
Back
Previous problem
Next problem
All textbooksYoung & Freedman Calc 14th EditionCh 36: DiffractionProblem 35

Chapter 35, Problem 35

In a two-slit interference pattern, the intensity at the peak of the central maximum is I0. (a) At a point in the pattern where the phase difference between the waves from the two slits is 60.0°, what is the intensity?

Verified Solution
Video duration:
2m
This video solution was recommended by our tutors as helpful for the problem above.
277
views
Was this helpful?

Video transcript

Hello, fellow physicists today, we're going to solve the following practice problem together. So first off, let's read the problem and highlight all the key pieces of information that we need to use in order to solve this problem. Two physics buddies perform a double slit experiment. They observe bright and dark fringes when light passes through the slits and falls on a flat observation screen, find the intensity when the phase difference between the waves from the two slits is 70.0 degrees. The intensity at the center of the central maximum is I subscript zero. OK. So we're given some multiple choice answers. Let's read them off to see what our final answer might be. A is 0.54 I zero B is 0.671 I zero C is 0.34 I zero D is 0.18 I zero where it's I subscript zero. OK. So first off, let us recall and use the equation for intensity and intensity states that its intensity I is equal to I subscript zero multiplied by cosine squared of data divided by two. OK. So since we are all of our final answers for the multiple choice are given as I subscript zero, you don't have to worry about finding a numerical value for that. So let's plug in 70 degrees for theta and solve for I. So I equals I zero multiplied by cosine squared 70.0 degrees divided by two. So when you plugged into a calculator, you should get your intensity to equal 0. I subscript zero, which is our final answer. OK. So that means that out of our multiple choice answers, the correct answer is B 0.671 I subscript zero. Thank you so much for watching. Hopefully that helped and I can't wait to see you in the next video. Bye.
Previous problemNext problem
Related Practice
Textbook Question
Coherent light with wavelength 450 nm falls on a pair of slits. On a screen 1.80 m away, the distance between dark fringes is 3.90 mm. What is the slit separation?
535
views
Textbook Question
Two slits spaced 0.450 mm apart are placed 75.0 cm from a screen. What is the distance between the second and third dark lines of the interference pattern on the screen when the slits are illuminated with coherent light with a wavelength of 500 nm?
330
views
Textbook Question
Coherent light of frequency 6.32 * 1014 Hz passes through two thin slits and falls on a screen 85.0 cm away. You observe that the third bright fringe occurs at ±3.11 cm on either side of the central bright fringe. (a) How far apart are the two slits? (b) At what distance from the central bright fringe will the third dark fringe occur?
443
views
Textbook Question
Two slits spaced 0.260 mm apart are 0.900 m from a screen and illuminated by coherent light of wavelength 660 nm. The intensity at the center of the central maximum 1u = 0°2 is I0. What is the distance on the screen from the center of the central maximum (a) to the first minimum
303
views
Textbook Question
Two slits spaced 0.260 mm apart are 0.900 m from a screen and illuminated by coherent light of wavelength 660 nm. The intensity at the center of the central maximum 1u = 0°2 is I0. What is the distance on the screen from the center of the central maximum (b) to the point where the intensity has fallen to I0>2?
333
views
Textbook Question
If the planes of a crystal are 3.50 Å (1 Å = 10-10 m = 1 Ångstrom unit) apart, (a) what wavelength of electromagnetic waves is needed so that the first strong interference maximum in the Bragg reflection occurs when the waves strike the planes at an angle of 22.0°, and in what part of the electromagnetic spectrum do these waves lie?
262
views