Question

54. A slit of width 'a' is illuminated by white light.
For what value of 'a' will the first minimum
for red light of wavelength 650 nm be at
0 = 15° ? (Given sin 15° = 0.2588)
(A) 10 um (B) 5 um
(C) 4.5 um (D) 2.5 um​

Answer 1

Answer:

answer is. D) 2.5

a 2.5

a5 can be 5 or 2.5