3.6 Polarisation

• What is polarisation defined as in physics?

  Restriction of oscillation direction
• In transverse waves, oscillations are perpendicular to the direction of energy transfer.


  True
• Give an example of a transverse wave.

  Light wave
• In longitudinal waves, oscillations are parallel to the direction of energy transfer.


  True
• What is the key difference in oscillation direction between natural and polarized light?

  Single vs. all directions
• Polarizers work by absorbing or reflecting light waves oscillating in all directions except one.

  True
• What are polarizers designed to allow through?

  Light in a specific direction
• When unpolarized light passes through a polarizing filter, the emerging light is polarized
• Transverse waves and longitudinal waves differ in their direction of oscillation.

  True
• In which direction does natural light oscillate?

  All directions
• Polarization is used in LCD screens to control the light passing through pixels.

  True
• In photography, polarizing filters reduce reflections and saturate colors
• Polarized light can be used in optical fiber communication systems to encode data.


  True
• Polarisation is the restriction of the direction of oscillation
• Match the wave type with its oscillation direction:

  Transverse Waves ↔️ Perpendicular

  Longitudinal Waves ↔️ Parallel
• Longitudinal waves have compressions and rarefactions
• Arrange the following types of light based on their oscillation direction:

  1️⃣ Natural Light: Oscillates in all directions

  2️⃣ Polarized Light: Oscillates in a single direction
• Methods of polarization include transmission through polarizers
• What happens to unpolarized light when it passes through a polarizing filter?

  It becomes polarized
• Polarizers absorb or reflect light waves oscillating in all directions except one.

  True
• What is polarization the process of restricting in transverse waves?

  Direction of oscillation
• An example of transverse waves is light
• Steps in the process of polarization using a polarizer:

  1️⃣ Unpolarized light enters the polarizer

  2️⃣ Waves oscillating in all directions are absorbed or reflected

  3️⃣ Light oscillates in a single plane
• What is the purpose of polarized sunglasses?

  Reduce glare
• How do LCD displays use polarized light to create images?

  Control light through pixels
• What does polarized light microscopy enhance in samples?

  Contrast