Monochromatic light (vacuum = 632 nm) shines on a soap film (n = 1.33) that has air on either side of it. The light strikes the film perpendicularly. What is the minimum thickness of the film for which constructive interference causes it to look bright in reflected light?

A flat piece of glass is held stationary and horizontal above the highly polished, flat top end of a 9.00-cm-long vertical metal rod that has its lower end rigidly fixed. The thin film of air between the rod and glass is observed to be bright by reflected light when it is illuminated by light of wavelength 515 nm. As the temperature is slowly increased by 25.5°C, the film changes from bright to dark and back to bright 200 times. What is the coefficient of linear expansion of the metal?

Light travelling from air hits a dangerous glycerol (n=1.45) spill on the top of a piece of pyrex glass (n=1.55). If a scientist observes dark spots from the glycerol spill, and the thickness of the film was measured to be 128 nm, determine the wavelength of light in air.

A child is playing with a bubble wand, which is a large rectangular wire frame that contains a soap film. The child holds the wand vertically, which causes the film to be thinner at the top and thicker at the bottom, forming a wedge shape. Assume a thickness of essentially zero at the top. White light shines on the film with approximately normal incidence. The child views the reflected light from the film and sees the first violet interference band at a distance of 3.00 cm from the top edge of the film. The index of refraction of the soap film is the same as that of water, n = 1.33, and the wavelength of violet light is 1 = 403 nm. (a) At what distance (in cm) from the top edge of the film does the child see the first red (A = 666 nm) interference band? cm (b) What is the thickness (in nm) of the soap film at the location of the first violet interference band? nm What is the thickness (in nm) of the soap film at the location of the first red interference band? nm (c) What is the wedge…