The angular width of a central max is 30° when the slit is illuminated by light of wavelength 6000 Å. Then the width of the slit will be approx.
Correct answer: B. 12 x 10^-7 m
- A. 12 x 10^-6 m
- B. 12 x 10^-7 m
- C. 12 x 10^-8 m
- D. 12 x 10^-9 m
Explanation
Angular width = 2θ = 30°∴ sin 30° = λ / a∴ a = λ / sin 30°= 6000 × 10⁻¹⁰ / sin 30°= 6000 × 10⁻¹⁰ / 1/2= 12000 × 10⁻¹⁰ m= 12 × 10⁻⁷ m
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Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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