Chapter 22 Electomagnetic Waves

Question 0

Is sound an electromagnetic wave? If not, what kind of wave is it?

Answer 0

No, sound is a mechanical wave. It can’t travel in a vacuum, requires matter.

Question 1

The electric field is an EM wave traveling north oscillates in an east-west plane. Describe the direction of the magnetic field vector in this wave.

Answer 1

The magnetic field is moving north and south, perpendicular to the current.

Question 2

Can EM waves travel through a perfect vacuum? Can sound waves?

Answer 2

EM waves can travel through a vacuum. Ex. Light

Sound can not travel through a vacuum b/c it’s a compressional wave.

Question 3

Are the wavelengths of radio and television signals longer or shorter than those detectable by the human eye?

Answer 3

Radio and micro waves have lower frequencies and longer wavelengths than visible light.
Visible light:
Red = lowest frequency & longest wavelength, closest to radio and micro waves in the spectrum