Question 1

According to Huygens’ principle, what happens at every point on a wavefront?

Accepted Answer

Each point acts as a source of new spherical wavelets.

Question 2

Which phenomenon observed in Young’s double-slit experiment provides evidence for the wave nature of light?

Accepted Answer

The appearance of an interference pattern of bright and dark fringes.

Question 3

A beam of light passes from air (index of refraction $$n_1) $$into glass (index $$n_2$$ \u003e $$n_1). $$According to Huygens’ principle, what happens to the wavelength and frequency of the light?

Accepted Answer

Wavelength decreases, frequency remains the same.

Question 4

Which equation correctly gives the condition for constructive interference in Young’s double-slit experiment?

Accepted Answer

$$d \sin 	heta = m \lambda$$

Question 5

A highway mirage is caused by:

Accepted Answer

A gradually changing index of refraction in heated air.

Question 6

Which of the following best describes the visible spectrum of light?

Accepted Answer

Wavelengths from 400 nm to 750 nm.

Question 7

Why does a prism split white light into a rainbow of colors?

Accepted Answer

Because the index of refraction varies with wavelength (dispersion).

Question 8

In a single-slit diffraction experiment, the condition for the first minimum in the diffraction pattern is:

Accepted Answer

$$a \sin 	heta = \lambda$$

Question 9

A diffraction grating produces sharper and more widely separated maxima than a double slit because:

Accepted Answer

It has a large number of equally spaced slits.

Question 10

A spectrometer can be used to measure the wavelength of light by:

Accepted Answer

Measuring the angle at which light is diffracted by a grating.

Question 11

Which of the following is a real-world example of thin film interference?

Accepted Answer

The colorful patterns seen in soap bubbles.

Question 12

If the slit separation in a double-slit experiment is halved, what happens to the angular separation between adjacent bright fringes?

Accepted Answer

It doubles.

Question 13

Which equation gives the relationship between the wavelength of light in two media with indices of refraction $$n_1$$ and $$n_2$$?

Accepted Answer

$$\frac{\$$lambda_2$$}{\$$lambda_1$$} = \frac{n_1$}{n_2$}$$

Question 14

In a diffraction grating, the condition for the $$mth $$order maximum is:

Accepted Answer

$$d \sin 	heta = m \lambda$$

Question 15

Which of the following best explains why rainbows form in the atmosphere?

Accepted Answer

Dispersion of sunlight in water droplets.

Question 16

A student observes a bright spot at the center of the shadow of a small circular disk. This is best explained by:

Accepted Answer

Diffraction of light around the disk.

Question 17

Which of the following is NOT a requirement for two light sources to be coherent?

Accepted Answer

They must have the same amplitude.

Question 18

In a double-slit experiment, if the wavelength of light is increased, what happens to the fringe spacing on the screen?

Accepted Answer

It increases.

Question 19

Which of the following best describes the effect of increasing the number of slits in a diffraction grating?

Accepted Answer

The maxima become narrower and more intense.

The Wave Nature of Light – Study Notes (Giancoli, Chapter 24)

Study Guide - Practice Questions

Study Guide - Flashcards