A soap bubble (n = 1.35) is floating in air. If the thickness of the bubble wall is 328 nm, which of the following wavelengths of visible light is strongly reflected?
a. 621 nm (orange)
b. 547 nm (green)
c. 590 nm (yellow)
d. 707 nm (red)
e. 429 nm (violet)
[Ques. 2] Upon reflection, light undergoes a 180 phase change:
a. always.
b. if the incident medium has the higher index of refraction.
c. if the incident medium has the lower index of refraction.
d. whenever the incident angle is less than the critical angle.
[Ques. 3] Light is reflecting off a wedge-shaped thin piece of glass producing bright and dark interference fringes. If a certain location has a bright fringe, a nearby point will have a dark fringe if the thickness of the glass increases by:
a. 1/8 of a wavelength of the light.
b. 1/4 of a wavelength of the light.
c. 1/2 of a wavelength of the light.
d. one wavelength of the light.
[Ques. 4] When light passes from a material with a high index of refraction into material with a low index of refraction:
a. none of the light is reflected.
b. some light is reflected without a change of phase.
c. some light is reflected with a 180 change of phase.
d. the light that is not reflected has a 180 change of phase.
[Ques. 5] The center spot of Newton's rings is dark. This destructive interference occurs because:
a. the two beams travel distances that are different by half a wavelength.
b. both waves change phase by 180 as they are reflected.
c. one beam changes phase by 180 when it is reflected.
d. both waves have a trough.
[Ques. 6] When light shines on a lens placed on a flat piece of glass, interference occurs which causes circular fringes called Newton's rings. The two beams that are interfering come:
a. from the top and bottom surface of the lens.
b. from the top surface of the lens and the top surface of the piece of glass.
c. from the bottom surface of the lens and the top surface of the piece of glass.
d. from the top and bottom surface of the flat piece of glass.
[Ques. 7] Two flat glass plates are in contact along one end and are separated by a sheet of tissue paper at the other end. A monochromatic source of wavelength 427 nm illuminates the top plate. If 11 dark bands are counted across the top plate, what is the paper thickness? (1 nm = 109 m)
a. 4.3E6 m
b. 1.7E6 m
c. 2.1E6 m
d. 2.6E6 m
e. 1.3E6 m
[Ques. 8] Two flat glass plates are in contact along one end and are separated by a sheet of paper 3.3 106 m thick at the other end. The top plate is illuminated by a monochromatic light source of wavelength 514 nm. How many dark parallel bands will be evident across the top plate? (1 nm = 109 m)
a. 7
b. 11
c. 6
d. 13
e. 9
[Ques. 9] Two closely spaced parallel glass plates are separated by 977 nm. What wavelength light source in the visible region (390 nm to 710 nm) will experience maximum transmission through the two plates?
a. 651 nm
b. 695 nm
c. 655 nm
d. 618 nm
e. 601 nm
[Ques. 10] A beam of light of wavelength 674 nm is incident along the normal to two closely spaced parallel glass plates. For what air gap separation between the plates will the transmitted beam be of maximum intensity? (1 nm = 109 m)
a. 169 nm
b. 674 nm
c. 337 nm
d. 843 nm
e. 506 nm
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