Electromagnetic Waves - Lesson Review
Define photon. What determines how much energy a photon has?
A photon is the name of the "packet" of energy given off when an electron returns to a lower energy level. The amount of energy in a photon depends on the frequency of electromagnetic radiation. The higher the frequency is, the more energy a photon has.
Explain how an electromagnetic wave begins and how it travels.
An electromagnetic wave begins when an electrically charged particle vibrates, causing its electric field to vibrate. The vibrating electric field then creates a vibrating magnetic field. These two vibrating fields combine to create an electromagnetic wave. The electric and magnetic fields of an electromagnetic wave occur at right angles to each. Both fields are also at right angles to the direction that the wave travels, so an electromagnetic wave is a transverse wave. However, unlike a mechanical transverse wave, an electromagnetic wave can travel across space without a medium as well as through a medium.
The wave-particle theory of light was developed by __________.
Einstein
What is the wave-particle theory of electromagnetic radiation?
The wave-particle theory of electromagnetic radiation is the theory that explains how electromagnetic radiation can behave as both a wave and a particle. When an electron returns to a lower energy level, it gives off a tiny "packet" of energy like a particle that travels as a wave
Definition: packet of electromagnetic energy Terms: a. photon b. electromagnetic wave c. magnetic field d. transverse wave e. electromagnetic radiation f. wave-particle theory g. electric field
a
Definition: wave that consists of vibrating electric and magnetic fields Terms: a. photon b. electromagnetic wave c. magnetic field d. transverse wave e. electromagnetic radiation f. wave-particle theory g. electric field
b
A vibrating electric field creates a: a. mechanical wave. b. charged particle. c. magnetic field. d. photon
c
Definition: invisible area of force surrounding a magnet Terms: a. photon b. electromagnetic wave c. magnetic field d. transverse wave e. electromagnetic radiation f. wave-particle theory g. electric field
c
What do radio waves and sound waves have in common? a. Both waves are transverse waves. b. Both waves are mechanical waves. c. Both waves transfer energy. d. Both waves need a medium.
c
An electromagnetic wave begins when a(n) __________ particle vibrates.
charged
An electromagnetic wave consists of a vibrating: a. magnetic field. b. electric field. c. particle of matter. d. two of the above
d
As an electromagnetic wave travels through space, it: a. becomes stronger. b. keeps changing direction. c. loses energy to the medium. d. spreads out over a larger area.
d
Definition: wave in which vibrations occur at right angles to the direction the wave travels Terms: a. photon b. electromagnetic wave c. magnetic field d. transverse wave e. electromagnetic radiation f. wave-particle theory g. electric field
d
Examples of electromagnetic waves include: a. radio waves. b. light. c. X rays. d. all of the above
d
When electromagnetic waves strike matter, they may: a. reflect. b. refract. c. diffract. d. all of the above
d
Which of the following statements about electromagnetic radiation is false? a. It provides virtually all the energy for life on Earth. b. It behaves like a wave most of the time. c. Sometimes it behaves like a particle. d. All of its wavelengths are harmful.
d
Definition: transfer of energy by waves such as radio waves and light Terms: a. photon b. electromagnetic wave c. magnetic field d. transverse wave e. electromagnetic radiation f. wave-particle theory g. electric field
e
Definition: explanation for how light can behave as both a wave and a particle Terms: a. photon b. electromagnetic wave c. magnetic field d. transverse wave e. electromagnetic radiation f. wave-particle theory g. electric field
f
All of the sun's electromagnetic radiation travels to Earth. - True or False
false
Both fields of an electromagnetic wave vibrate in the same direction that the wave travels. - True or False
false
Electromagnetic waves cannot travel through matter - True or False
false
The human eye can detect all frequencies of electromagnetic waves. - True or False
false
When electrons return to lower energy levels, they give off particles of matter. - True or False
false
The amount of energy in a photon depends on the __________ of electromagnetic radiation.
frequency
Definition: invisible area of force surrounding a charged particle Terms: a. photon b. electromagnetic wave c. magnetic field d. transverse wave e. electromagnetic radiation f. wave-particle theory g. electric field
g
Unlike mechanical waves, electromagnetic waves can travel across __________.
space
The most important source of electromagnetic radiation on Earth is the __________.
sun
When microwaves strike food in a microwave oven, the waves are converted to __________ energy.
thermal
Waves in a rope and electromagnetic waves are both __________ waves.
transverse
Einstein explained how light can behave both as a wave and as a particle. - True or False
true
Electromagnetic waves are used for communications, cooking, and medicine. - True or False
true
Electromagnetic waves may spread out and travel around obstacles. - True or False
true
The two fields of an electromagnetic wave occur at right angles to each other. - True or False
true
When a charged particle vibrates, it causes the electric field around it to vibrate. - True or False
true
