NEET 2026
- Exam
- NEET
- Year
- 2026
- Subject
- Physics
- Chapter
- Chapter
NEET 2026 · Physics · Chapter
In a Young's double slit setup, the slits are illuminated by a...
In a Young's double slit setup, the slits are illuminated by a white light source. Which colour of light will form the first-order bright fringe closest to the central white maximum on the viewing screen?
Options
- AViolet
- BYellow
- CRed
- DGreen
Correct answer
A. Violet
Step-by-step solution
The position of the -th order bright fringe from the central maximum in Young's double slit experiment is given by .
For the first-order bright fringe, , which gives .
The distance is directly proportional to the wavelength of the light.
Among the colours of visible light, violet has the shortest wavelength ().
Since violet light has the minimum wavelength, its first-order bright fringe will be formed at the minimum distance from the central maximum. Therefore, violet will be closest to the central white maximum.
Answer: Violet
For the first-order bright fringe, , which gives .
The distance is directly proportional to the wavelength of the light.
Among the colours of visible light, violet has the shortest wavelength ().
Since violet light has the minimum wavelength, its first-order bright fringe will be formed at the minimum distance from the central maximum. Therefore, violet will be closest to the central white maximum.
Answer: Violet