4.3 Polarisation

An optically active substance is a substance that

• has a refractive index that depends on the plane of polarisation of incident light

• completely absorbs incident unpolarised light.

• rotates the plane of polarization of incident polarized light.

• polarizes unpolarized light.

Polarized light of intensity I₀ is incident on a polarising filter. The angle between the plane of polarisation of the incident light and the transmission plane of the polariser is θ. Which graph shows how the intensity I of the light transmitted through the polariser varies with θ?

• A

• B

• C

• D

Unpolarised light of intensity I₀ is incident on a polariser with a vertical transmission axis. The transmitted light is incident on a sheet of material X. After transmission through X the intensity of the light is I₀/2.

It is suggested that X could be

I. a polarizer with vertical transmission axis

II. a polarizer with horizontal transmission axis

III. non polarizing glass.

Which of the above suggestions is/are correct?

• I and III only

• I only

• II only

• I and II only

Tags

NGSS.HS-PS4-1

Two polarizing filters are set up so the transmitted light is at a maximum intensity.

Through which angle should polariser 2 be rotated so that no light is transmitted?

• 45º

• 60º

• 90º

• 180º

Tags

NGSS.HS-PS4-5

Properties of waves are

I. polarization

II. diffraction

III. refraction

Which of these properties apply to sound waves?

• I and II

• II and III

• I and III

• All of them