Author Question: A planoconvex lens of radius R and index of refraction n is placed curved side down on flat glass ... (Read 73 times)

nelaaney · **on:** Jul 28, 2018

A planoconvex lens of radius R and index of refraction n is placed curved side down on flat glass surface. This configuration is being used to measure the wavelength of light produced by a particular light source. If the radius of the dark rings produced by interference is r, what is the wavelength of the light? Assume the setup is in air.
1. rn/mR
2. Rn/mr
3. mR/nr2
4. R2/mR

Question 2

Two glass slides are separated by a thin layer of plastic. The glass has an index of refraction nglass and the plastic has an index nplastic. The two indices are not equal. If nplastic = 1.50, for what minimum non-zero thickness of plastic will the transmitted light be for a beam of wavelength 600 nm?
1.400 nm
2.200 nm
3.100 nm
4.One needs to know which of the indices is the greater to solve this.