Exam 35: Interference

Waves from two slits are in phase at the slits and travel to a distant screen to produce the second minimum of the interference pattern. The difference in the distance traveled by the wave is:

If the wavelength of a particular beam of light in vacuum is λ, and the index of refraction of a material is n, what is the wavelength of the light in the material?

Light from a point source X contains only blue and red components. After passing through a mysterious box, the light falls on a screen. Red and blue hands are observed as shown. The box must contain:

The light waves represented by the three rays shown in the diagram all have the same frequency. 4.7 wavelengths fit into layer 1, 3.2 wavelengths fit into layer 2, and 5.3 wavelengths fit into layer 3. Rank the layers according to the speeds of the waves, least to greatest.

An air wedge is formed using two glass plates that are in contact along their left edge. When viewed by highly monochromatic light, there are exactly 4001 dark bands in the reflected light. The air is now evacuated (with the glass plates remaining rigidly fixed) and the number of dark bands decreases to exactly 4000. The index of refraction of the air is:

Two light waves are initially in phase and have the same wavelength, 470 nm. They enter two different media of identical lengths of 2.50 µm. If n₁ = 1.2 and n₂ = 1.5, what is the effective phase difference of the waves when they exit the media?

Consider (I) the law of reflection and (II) the law of refraction. Huygens' principle can be used to derive:

Units of "optical path length" are:

Waves from two slits are in phase at the slits and travel to a distant screen to produce the third bright fringe of the interference pattern. The difference in the distance traveled by the waves is:

The three factors that determine the interference of reflected waves from a thin film are:

In a thin film experiment, a wedge of air is used between two glass plates. If the wavelength of the incident light in air is 480 nm, how much thicker is the air wedge at the 16th dark fringe than it is at the 6th?

A light wave with an electric field amplitude of 2E₀ and a phase constant of zero is to be combined with one of the following waves. Which of these combinations produces the least intensity?

A "wave front" is a surface of constant:

Interference of light is evidence that:

Two point sources, vibrating in phase, produce an interference pattern in a ripple tank. If the frequency is increased by 20%, the number of nodal lines:

Red light is viewed through a thin vertical soap film. At the third dark area shown, the thickness of the film, in terms of the wavelength $\lambda$ within the film, is:

A lens with a refractive index of 1.5 is coated with a material of refractive index 1.2 in order to minimize reflection. If $\lambda$ denotes the wavelength of the incident light in air, what is the thinnest possible such coating?

Three experiments involving a thin film (in air) are shown. If t denotes the film thickness and $\lambda$ denotes the wavelength of the light in the film, which experiments will produce constructive interference as seen by the observer?

In a Young's double-slit experiment, the slit separation is doubled. This results in:

In a Young's double-slit experiment, the separation between slits is d and the screen is a distance D from the slits. D is much greater than d and $\lambda$ is the wavelength of the light. The number of bright fringes per unit length on the screen is: