Question Detail
Question
In a Young's interference experimental arrangement, light of wavelength 589 nm is incident on the diffraction grating. If the separation between slits is 1 mm and the screen is placed 1 m away, up to what order of bright fringes can be seen on the screen?
Correct Answer
Option D is the correct answer.
Detailed Explanation
The condition for bright fringes is d sin θ = mλ. The maximum order (m_max) occurs when sin θ = 1 (i.e., θ = 90°). So m_max = d/λ = (1 × 10^-3) / (589 × 10^-9) = 1697.8 ≈ 1.7 × 10^3.
Hint
The highest order is limited by sin θ ≤ 1. Use m_max = d/λ.