Diffraction due to a single slit
- A linear aperture whose width is 0.02 cm is placed immediately in front of a lens of focal length 60 cm. The aperture is illuminated normally by a parallel beam of wavelength 5×10^-5 cm. The distance of the first dark band of the diffraction pattern… Answer: 3. 0.15 cm For the first dark band in single-slit diffraction, asinθ=λ . sinθ=dfrac5×10⁻⁵0.02=2.5×10⁻³ , a small angle. Distance on... 1
- In a diffraction pattern due to a single slit of width 'a', the first minimum is observed at an angle 30^° when light of wavelength 5000 Å is incident on the slit. The first secondary maximum is observed at an angle of : Answer: 4. sin⁻¹(3/4) Key idea: single-slit minima satisfy asinθ=nλ ; secondary maxima are approximately at asinθ=(n+1/2)λ . First minimum a... 1