Wave Optics

JEE Main level, single correct, medium

90 of 191

Question 90 of 191

If the source of light used in a Young's double slit experiment is changed from red to violet:

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Answer: (A) consecutive fringe lines will come closer.

β=λ⋅Dd\beta =\dfrac{\lambda \cdot D}{d}
λR>λV{\lambda }_{R}\gt {\lambda }_{V}
βR=λRDd{\beta }_{R}=\dfrac{{\lambda }_{R}D}{d} and βV=λVDd{\beta }_{V}=\dfrac{{\lambda }_{V}D}{d}
βR>βV{\beta }_{R}\gt {\beta }_{V}
Fringe pattern will shrink.

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