In Young’s double slit experiment, if the separation between the slits is doubled (within the wavelength range), then the fringe width is:

Correct option is B

The correct answer is (b) Halved
Explanation:
The fringe width β in Young's double slit experiment is given by the formula:
β = λD / d
Where:
• λ = wavelength of light
• D = distance between slits and screen
• d = distance between the two slits
If the slit separation d is doubled, then the fringe width β will become half, because fringe width is inversely proportional to slit separation.
So the correct conclusion should be:
Fringe width is halved when slit separation is doubled.
Information Booster:
• Fringe width increases when slit separation decreases, and vice versa.
• If λ or D increases, β increases.
• If d increases, β decreases.