Question Detail
Question
In Young's experiment, if two slits are 0.04 mm apart, the screen is 2m away, and the third bright fringe from the center is displaced 8.3 cm, what is the wavelength of the incident light?
Correct Answer
Option B is the correct answer.
Detailed Explanation
Given: d = 0.04 mm = 0.04 × 10-3 m, x = 2 m, n = 3 (for third bright fringe), y = 8.3 cm = 0.083 m. The formula for bright fringes is yd/x = nλ. Rearranging for λ: λ = (yd) / (nx) λ = (0.083 m × 0.04 × 10-3 m) / (3 × 2 m) λ = (3.32 × 10-6) / 6 λ = 0.5533 × 10-6 m = 553.3 nm. Option B (553 nm) is the closest.
Hint
Use the formula for bright fringes: yd/x = nλ. Ensure all units are consistent (e.g., meters).