Question

[2pt] An electromagnetic wave transports energy. How do the electric and magnetic field parts of the wave compare in contributing to this energy?

A) It depends on the type of EM wave.

B) The B-field carries all the energy.

C) The E-field carries all the energy.

D) They each carry half the energy.

E) The B-field has a fraction 1/c of the energy.

. [2pt] A beam of white light travels from air (n=1) into water (n=1.33), entering the water at an angle perpendicular to the surface. The white light will:

A) pass straight through into the water, remaining white.

B) pass straight through into the water and will seperate into a rainbow.

C) curve away from the normal into the water and will seperate into a rainbow.

D) curve away from the normal into the water, remaining white.

[2pt] To some degree you can steer a beam of light around tight corners using a fiber optic cable. The physics behind this is best described by:

A) diffraction.

B) the critical angle.

C) Brewster’s angle.

D) double slit interference.

. [2pt] Given any lens and a real object arranged so that a virtual image is formed, the image is .

A) never inverted B) always inverted C) inverted if shrunk D) inverted if enlarged

Answer 1