OAT Physics: Optics and Waves Questions and Answers

Question 1

A beam of monochromatic light travels from water (n ≈ 1.33) into an unknown transparent medium.
If the angle of incidence in the water is 30° and the angle of refraction in the new medium is 22°, what is the index of refraction of the unknown medium?

Accepted Answer

1.80

Answer

1.00

Answer

1.33

Answer

1.52

Question 2

An object is placed 40 cm in front of a converging lens, which forms a real, inverted image 60 cm on the other side of the lens. What is the focal length of this lens?

Accepted Answer

24 cm

Answer

12 cm

Answer

50 cm

Answer

100 cm

Question 3

Which of the following changes will increase the angular separation (θ) between the central maximum (m=0) and the first-order maximum (m=1) in a diffraction grating experiment?

Accepted Answer

Using a grating with more lines per millimeter.

Answer

Decreasing the wavelength of the light used.

Answer

Increasing the distance between the grating and the screen.

Answer

Decreasing the intensity of the light source.

Question 4

A stationary observer hears a fire truck's siren. As the fire truck moves away from the observer at a constant speed, which of the following properties of the sound wave perceived by the observer decreases?

Accepted Answer

Frequency

Answer

Wavelength

Answer

Speed of the wave

Answer

Amplitude

Question 5

Which of the following statements is true for all types of electromagnetic waves, including radio waves, visible light, and X-rays, when traveling in a vacuum?

Accepted Answer

They all have the same speed.

Answer

They all have the same frequency.

Answer

They all have the same wavelength.

Answer

They all carry the same amount of energy per photon.

Question 6

Unpolarized light with an initial intensity of I₀ is incident on an ideal polarizing filter. What is the intensity of the light that passes through the filter?

Accepted Answer

I₀ / 2

Answer

I₀

Answer

I₀ / √2

Answer

0

A beam of monochromatic light travels from water (n ≈ 1.33) into an unknown transparent medium.If the angle of incidence in the water is 30° and the angle of refraction in the new medium is 22°, what is the index of refraction of the unknown medium?

A beam of monochromatic light travels from water (n ≈ 1.33) into an unknown transparent medium.
If the angle of incidence in the water is 30° and the angle of refraction in the new medium is 22°, what is the index of refraction of the unknown medium?