NEET-XII-Physics
17: Light Waves
- #9Find the angular separation between the consecutive bright fringes in a Young’s double slit experiment with blue-green light of wavelength 500 nm. The separation between the slits is
2·0×10-3 m.Ans : Given:
Wavelength of the blue-green light, `` \lambda =500\times {10}^{-9}\,\mathrm{\,m\,}``
`` ``
Separation between two slits, `` d=2\times {10}^{-3}\,\mathrm{\,m\,},``
Let angular separation between the consecutive bright fringes be θ.
`` \,\mathrm{\,Using\,}\theta =\frac{\beta }{D}=\frac{\lambda D}{dD}=\frac{\lambda }{d},\text{we get:}``
`` \theta =\frac{500\times {10}^{-9}}{2\times {10}^{-3}}``
`` =250\times {10}^{-6}``
`` =25\times {10}^{-5}\,\mathrm{\,radian\,}\,\mathrm{\,or\,}0.014°``
Hence, the angular separation between the consecutive bright fringes is 0.014 degree.
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