?

SAT® Subject Test in Physics

Free Version

Upgrade subject to access all content

Moderate

Seeing the Light

SATPHY-M2EXQJ

Ordinary light passes through two polarizing filters. The filters have been rotated so that their polarizing axes are oriented at $90^{\circ}$ to each other, and no light gets through both of them.

By adding a third polarizing filter so that there are three in a row, how might one cause light to pass through the three filters?

A

Orient the third filter so that its polarizing axis is rotated $45^{\circ}$ clockwise relative to the first and place it in front of the first.

B

Orient the third filter so that its polarizing axis is rotated $45^{\circ}$ counter-clockwise relative to the second and place it in back of the second.

C

Orient the third filter so that its polarizing axis is rotated $45^{\circ}$ clockwise relative to the first and place it in between the two filters.

D

Orient the third filter so that its polarizing axis is rotated $90^{\circ}$ clockwise relative to the first and place it in front of the first.

E

Both $A$ and $B$ will work to allow light through.