The figure (Figure 1) shows the interference pattern obtained in a double-slit e
ID: 1454870 • Letter: T
Question
The figure (Figure 1) shows the interference pattern obtained in a double-slit experiment with light of wavelength lambda. Identify the fringe or fringes that result from the interference of two waves whose phases differ by exactly 2 lambda. Enter the letter(s) indicating the fringe(s) in alphabetical order. For example, if you think that fringes A and C are both correct, enter AC. Part B The same double-slit experiment is then immersed in water (with an index of refraction of 1.33) and repeated. When in the water, what happens to the interference fringes? They are more closely spaced than in air by a factor of 1.33. They are more widely spaced than in air by a factor of 1.33. O They are spaced the same as in air. O They are shifted upward. Q They are shifted downward.Explanation / Answer
AD
A and D fit this description. You should notice that they are 4 light bands apart. Each band is 1/2 , so the 4 bands equal 2
In a double-slit experiment, when two waves reach the screen shifted by an integer number of wavelengths, such as 2 or -2, at that point the waves are in phase and interfere constructively. Their amplitudes add up and the resulting band, or fringe, on the screen is a bright region where light intensity is at a maximum. Note that several bright fringes can be seen in the interference pattern shown in the figure. Each of them is produced by waves that are shifted by a different (integer) number of wavelengths. Choose those that correspond to a path difference of .(+-)2
part b) They are more closely spaced than in air by a factor of 1.33.
When the experiment is immersed in water, the wavelength of light decreases because the index of refraction of water is higher than that of air. Since the positions of the centers of the bright bands depend on the wavelength of light, light with a smaller wavelength will produce interference fringes that are more closely spaced; the higher the index of refraction, the more closely spaced are the fringes.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.