COMEDK 2023 Shift 1 Paper

The wavelength of light changes when it moves from one medium to another due to a change in its speed. The speed of light in any medium is given by v=‌

c

n

, where v is the speed of light in the medium, c is the speed of light in vacuum, and n is the refractive index of the medium.
The wavelength of light in any medium can be related to its wavelength in vacuum by the equation:
λ‌medium ‌=‌

λ‌sacum ‌

n

=‌

λak

n

Given that the refractive index of air is approximately 1 (i.e., n‌air ‌≈1 ), we can use the given refractive index of the new medium ( n‌medium ‌=1.5 ) to find the new wavelength in that medium.
Let the wavelength of the light in air be λ‌air ‌=600‌nm and in the new medium let it be λ‌medium ‌. Substituting the given values into the equation, we get:
λ‌medium ‌=‌

600‌nm

1.5

=400‌nm
Therefore, the wavelength of the light in the new medium with a refractive index of 1.5 will be 400‌nm. Hence, the correct answer is Option D, 400‌nm.