Answer Happy

a) This image suffers from chromatic aberrations. Explain: - The link between dispersion (nommal or anomalous) and chromatic aberrations. How are chromatic aberrations in the lens of the human eye corrected? b) A well collimated ray of monochromatic light is incident on a glass slab at an incidence angle of 15.0°. The refracted ray inside the glass slab is at an angle of 11.2º. What is the refractive index of the glass? What is the phase velocity of light inside the glass? Absorption spectrum of kets.caree lance 200 300 300 600 Welonghinn THE CANDIDATE MUST CHECK THAT THE ASSIGNMENT SET IS COMPLETE The figure shows the absorption spectrum of beta-carotene, the semi-conducting organic pigment that gives carrots their vivid orange colour. c) Based on the spectrum, explain why carrots are indeed orange. d) What is the size of the bandgap for beta-carotene in units of electron-volts? What is the corresponding photon wavelength? What happens to photons that encounter the pigment if they have an energy 1) lower, or ii) higher than the bandgap energy? (ignore polarization and orientation effects). e) Considering still a crystal of beta-carotene as in (). Write down the Beer-Lamberts law for absorption of monochromatic light by a beta-carotene crystal of length d along the light propagation direction Comment specifically on where the wavelength dependence appears in the equation for the beta-carotene pigment. f) A commonly used wavelength of the incident light for Raman spectroscopy is 785 nm. Describe qualitatively what kind of information that can be obtained for beta-carotene using i = 785 nm.