1.

The two slits in an interference experiment are illuminated by light of wavelength 5600 A. Deter-mine the path difference and phase difference between the waves arriving at the centre of the eighth dark fringe on the screen.

Answer»

Data : λ = 5600 A = 5.6 × 10-7 m

Order of the dark fringe is 8,

∴ m = 8

For the fringe to be dark, path difference

= (2m – 1) \(\cfrac λ2\)

∴ Path difference, ∆l = (2 × 8 – 1) \(\cfrac λ2\) = 7.5λ

= 7.5 × 5.6 × 10-7 m

= 4.2 × 10-6 m

Phase difference, φ = \(\cfrac{2\pi}λ\) x ∆l

\(\cfrac{2\pi}{5.6\times10^{-7}}\) × 4.2 × 10-6 = 15π



Discussion

No Comment Found

Related InterviewSolutions