Light I: Particle or Wave?

"Refraction" of light occurs when

• a.light bounces off a surface.
• b.light bends around corners or obstacles.
• c.light changes direction due to a change in speed.
• d.light waves add together to make a new wave with larger amplitude.

"Diffraction" of light occurs when

• a.light bounces off a surface.
• b.light bends around corners or obstacles.
• c.light changes intensity when passing from one material into another.
• d.light waves add together to make a wave with larger amplitude.

For diffraction of a wave to occur,

• a.the wave must be a sound wave.
• b.the wave must be traveling from a less dense to a denser material.
• c.the wave must be traveling slower than the speed of light in a vacuum.
• d.the wave must encounter an obstacle that is comparable in size to the wavelength of the wave.

"Constructive" and "destructive" interference refer to the phenomenon of

• a.waves adding together or canceling each other out when they are superimposed.
• b.waves traveling different distances.
• c.waves bending around obstacles.
• d.waves changing direction when moving from one material to another.

Young found that bright and dark spots appeared on the screen because of

• a.holes in a piece of paper.
• b.bright and dark lights shining on the screen.
• c.constructive and destructive interference.
• d.spectral lines.

Constructive interference occurs when the difference in path lengths traveled by two light rays is

• a.an integer multiple of the half-wavelength of the light.
• b.zero or an integer multiple of the wavelength of the light.
• c.anything other than zero.
• d.exactly zero.

Destructive interference occurs when the difference in path lengths traveled by two light rays is

• a.integer multiple of the half-wavelength of the light.
• b.zero or an integer multiple of the wavelength of the light.
• c.anything other than zero.
• d.exactly zero.