White light consisting of wavelengths ranging from 400nm to…

White light consisting of wavelengths ranging from 400nm to 700 nm is incident upon a diffraction grating having 600 lines/mm. The first order spectrum extends over a range of angles on a screen. Next, the grating is removed and replaced with one having 900 lines/mm. Which of the following statements is correct about the range of angles comprising the first order spectrum?

Two glass panes each 1.0 cm thick are separated by a thin la…

Two glass panes each 1.0 cm thick are separated by a thin layer of oil with a thickness of 1.0 cm. The index of refraction of the oil is 1.5. Light with a wavelength of 530 nm in a vacuum travels from point A to point B in 0.14 ns. What is the index of refraction for the glass?