At the first minimum adjacent to the central maximum of a single-slit diffraction pattern the phase difference between the Huygens wavelet from the edge of the slit and the wavelet from the mid-point of the slit is In a diffraction pattern due to a single slit of width a the first minimum is observed at an angle 30 degree∘ when light of wavelength 5000 Å is incident on the slit. The first secondary minimum is observed at an angle of August 20, 2020 Category: Chapter 32 - Ray Optics , NEET Last 32 Years Solved 1988 - 2019 Physics and Chemistry Video Solutions , Physics , Facebook Messenger WhatsApp Share this:TwitterFacebook Related