Refraction of light test questions - Higher Physics Revision

1

Which of the statements below best describes the refractive index of a material?

Refractive index of a material is the ratio of the angle of incidence to the angle of refraction in the material

Refractive index of a material is the ratio of the sine of angle of incidence to the sine of angle of refraction in the material

Refractive index of a material is the ratio of the sine of angle of refraction to the sine of angle of incidence in the material

2

How does the refractive index of air compare to the refractive index of empty space (vacuum)?

Greater

Approximately the same

Less

3

How does the refractive index of a material relate to the speed of light?

The ratio of speed of light in vacuum to the speed of light in the material

The difference between the speed of light in vacuum and the speed of light in the material

The ratio of speed of light in air to the speed of light in the material

4

What is the effect on wavelength when light enters a material from air?

Wavelength is increased due to refraction

Wavelength is unchanged due to special relativity

Wavelength is decreased due to refraction

5

How does the refractive index of a material change with the frequency of light passing through it?

Refractive index is directly proportional to frequency of light

Refractive index is inversely proportional to frequency of light

Refractive index slightly increases as the frequency of light increases

6

A student is investigating the effect that a semi-circular plastic block has on a ray of blue light (see the diagram below).

A ray of blue light leaves a semi-circular block. It travels at 25 degrees from the normal inside the block. It travels at 40 degrees from the normal outside the block.

The student notes that when the angle of incidence inside the plastic is \(25.0^{\circ}\) the angle of refraction in air is \(40.0^{\circ}\).

Calculate the refractive index of the plastic for the blue light.

1.52

1.48

3.62

7

Calculate the critical angle of the plastic for the blue light.

\[44.4^{\circ}\]

\[52.7^{\circ}\]

\[41.1^{\circ}\]

8

Which of the following statements is true for total internal reflection?

Occurs only if the angle of incidence is less than the critical angle

Reflects the majority of light back into the material

The angle of reflection is equal to the angle of incidence

9

A ray of red light is incident on a triangular prism made from clear plastic (as shown in the diagram below).

The refractive index of the plastic is 1.46 for the red light.

Calculate the angle of refraction as the ray of red light leaves the prism.

Triangle with three 60 degree internal angles. Red light ray hits side at 70 degree angle to normal. Refracted, passes through triangle and refracted again at other side, leaves at unspecified angle.

This is a challenging “A grade” question requiring problem solving as well as subject knowledge.

\[23^{\circ}\]

\[30^{\circ}\]

\[35^{\circ}\]

10

Which diagram correctly identifies angles of incidence and refraction at a boundary between air and glass?

Light beam goes from air into glass. Normal is perpendicular to glass. Angle of incidence between glass and beam. Angle of refraction between normal and light beam.

Light beam goes from air into glass. Normal is perpendicular to glass. Angle of incidence between beam and normal. Angle of refraction between light beam and glass surface.

Light beam goes from air into glass. Normal is perpendicular to glass. Angle of incidence between beam and normal. Angle of refraction between normal and light beam.