Lecture 7

Question 1

How is polarisation achieved

Answer 1

By passing waves through a grid, only the waves that can for through the slits can continue

Question 2

Parallel filters?

Answer 2

No change in intensity after second filter

Question 3

Perpendicular filters:

Answer 3

No transmission

Question 4

Production of polarising filter

Answer 4

-Polyvinyl alcohol is stretched into a thin sheet.

• The molecules are straightened into chains lying parallel to the direction of stretch.

•Dipped in iodine to create a polarising filter.

Question 5

Production of polarising filter

Answer 5

-Polyvinyl alcohol is stretched into a thin sheet.

• The molecules are straightened into chains lying parallel to the direction of stretch.

•Dipped in iodine to create a polarising filter.

Question 6

Some practical implications

Answer 6

•Fishing/driving
•Reflected light from some surfaces is horizontally polarised
•Polarised glasses only allow vertically polarised light through, this reduces glare effects
-sunglasses
•3D cinema and TV
•The 2 views are presented with light of different polarisations.

Question 7

Some practical implications

Answer 7

•Fishing/driving
•Reflected light from some surfaces is horizontally polarised
•Polarised glasses only allow vertically polarised light through, this reduces glare effects
-sunglasses
•3D cinema and TV
•The 2 views are presented with light of different polarisations.