A puddle of water (n = 1.33) is covered with a very thin layer of light oil (n = 1.20). What is the minimum thickness the oil in the region that does not reflect light with a wavelength of 550 nm?

Answer 1

A puddle holds 150 g of water. If 0.50 g of water evaporates from the surface, what is the approximate temperature change of the remaining water? (Lv = 540 cal/g)