In a Young's double slit experiment, the slits are separated by 0.2 mm. If the slits separation is increased to 0.4 mm, the percentage change of the fringe width is:
- (A)
- (B)
- (C)✓ Correct
- (D)
Answer: (C)
Solution
The fringe width in a double-slit pattern is , so it is inversely proportional to the slit separation. Doubling the separation from mm to mm halves the fringe width. The fractional change is a decrease of in the fringe width.
JEE Main · 2025 · 04 Apr 2025 · Shift 1 · Single correct option