PhysicsLAB: Polarization

	The amplitude of a light wave has magnitude and direction, and can be represented by a vector. Polarized light vibrates in a single direction and is represented by a single vector. To the left the single vector represents vertically polarized light. The vibrations of non-polarized light are equal in all directions. There are as many vertical components as horizontal components. The pair of perpendicular vectors to the right represents non-polarized light.

Refer to the following information for the next three questions.

In the sketch below non-polarized light from a flashlight strikes a pair of Polaroid filters.

Light is transmitted by a pair of Polaroids when their axes are

alignedcrossed at right angles

and light is blocked when their axes are

alignedcrossed at right angles

Transmitted light is polarized in a direction _____ the polarization axis of the filter.

the same asdifferent than

Refer to the following information for the next two questions.

Consider the transmission of light through a pair of Polaroids with polarization axes at 45º to each other. Although in practice the Polaroids are one atop the other, we show them spread out side by side below.


(a) Non-polarized light is represented by its horizontal and vertical components.	(b) These components strike filter A.	(c) The vertical component is transmitted, and	(d) falls upon filter B	(e) This vertical component is not aligned with the polarization axis of filter B, but it has a component that is - component t - transmitted.

The amount of light that gets through Filter B, compared to the amount that gets through Filter A is

morelessthe same

The component perpendicular to t that falls on Filter B is also

also transmittedabsorbed

Refer to the following information for the next three questions.

Below are a pair of Polaroids with polarization axes at 30º to each other. Discuss with your partner the orientation of the vectors and their appropriate components, as illustrated in previous question, to produce the specific vector that emerges at e.


a	b	c	d	e

The correct diagram for step c would be a

horizontal vectorvertical vector

The correct diagram for step e would be a

vector oriented at 30ºvector oriented at 120º

The amount of light that gets through the Polaroids at 30º, compared to the amount that gets though the 45º Polaraids is

lessmorethe same

Refer to the following information for the next three questions.

In Figure 27.19 in your textbook there is a picture showing the smile of Ludmila Hewitt emerging through three Polaroids. Discuss with your partner the orientation of the vectors and their appropriate components to produce the specific vector that emerges for this three-Polaroid system.


a	b	c	d	e	f	g

The correct diagram for step c would be a

horizontal vectorvertical vector

The correct diagram for step e would be a

vector oriented at 45ºvector oriented at 135º

The correct diagram for step g would be a

horizontal vectorvertical vector

Refer to the following information for the next question.

A novel use of polarization is shown above. How do the polarized side windows in these next-to-each-other houses provide privacy for the occupants? Who can see what?