Diffraction gratings are usually described not by the separation between adjacent lines but by the number of lines per centimeter. What is the maximum number of lines per centimeter a diffraction grating can have and produce a complete first-order spectrum for visible light? Assume visible light has a range of 400 nm to 700 nm.

A blackbody radiator in the shape of a sphere has a surface area of 152 If it has a temperature of 1200 K how much energy does it emit per second? If the sun emits light with a peak wavelength of 500 nm. What is the temperature of the sun? Two slits, 0.5 mm apart, are placed at a distance of 1.5 meters from a screen. Light of 300 nm illuminates the two slits and an interference pattern is observed on the screen.  What is the distance between the central bright spot and the first bright spot on either side?

A physicist is calibrating a spectrometer that uses a diffraction grating to separate light in order of increasing wavelength  (?A,?B, and ?C). He observes three distinct first-order spectral lines at the following respective angles ?m (where m denotes order). ?1 = 12.8°, ?1 = 14.2°, ?1 = 15.0° (a)If the grating has 3,760 grooves per centimeter, what wavelength (in nm) describes each of these spectral lines? at ?1 = 12.8°    ?A=         nm ?1 = 14.2°       ?B=         nm ?1 = 15.0°        ?C=.        nm (b) At what angle (in degrees) would each of these lines be found in the second-order spectrum? for ?A      ?2=   ° for ?B      ?2=    ° for ?C     ?2=   °