Wavelength of X-rays falling at a glancing angle of 30° on a crystal with atomic spacing 2x10^(-10) m for the first-order diffraction is
Correct answer: C. 0.02x10^(-10) m
- A. 4x10^(-10) m
- B. 1000 Angstro-2x10^(-10) m
- C. 0.02x10^(-10) m
- D. 20x10^(-10) mm
Explanation
Explanation: For the first-order diffraction, the Bragg's law is given by 2dsinθ=mλ, where d is the spacing between atomic planes, θ is the glancing angle, m is the order of diffraction, and λ is the wavelength.Rearranging the formula for λ: λ=m2dsinθ . Substituting the given values (d=2×10−10 m, θ=30∘, and m=1 for the first order), we get λ=0.02×10−10 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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