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Answer the following.
Student 1 and Student 2 conducted experiments using coherent sources of light, with Student 1 using…
Student 1 and Student 2 conducted experiments using coherent sources of light, with Student 1 using a single slit and Student 2 using a double slit.
Student 2 observes 10 fringes within a specific portion of the screen using the same monochromatic source of light. If he were to immerse his entire experimental setup in a liquid of refractive index $5/3$, what alteration should he make to the distance of the screen to maintain the same number of fringes?
Answer
Answer
Official answer keyNew wavelength $= \frac{\lambda}{n}$
$500 \div \frac{5}{3}$
D has to be increased 5/3 times as fringe width $= \frac{\lambda D}{d}$.
Final answer: D is to be increased 5/3 times
From ISC 2025 Practice Physics, question 92(d).