Chapter 1: Electromagnetic waves Flashcards
Chapter 1: A
Define a “wave.”
A wave is defined as the net transfer of energy (via oscillations) from one location to another without the net transfer of matter.
Chapter 1: A
Define a transverse wave
A transverse wave is a transmission of energy where particles oscillate perpendicularly to the direction in which the wave propagates.
Chapter 1: A
Define a longitudinal wave
A longitudinal wave transmits energy where particles oscillate parallel to the direction in which the wave propagates.
The oscillations of a longitudinal are also referred to as compression’s.
Chapter 1: A
Define an electromagnetic wave
An electromagnetic wave is a wave created due to the perpendicular oscillations of an electric and magnetic field. Hence, being classified as a transverse wave.
All wavelengths of electromagnetic radiation travel at a constant speed of 3 x 10^8 meters per second in a vacuum.
Chapter 1: A
Define a vacuum
A vacuum (in physics) is defined as a region or location which occupies no matter.
Chapter 1: A
Define a mechanical wave
A mechanical wave is created via the oscillations of particles (or matter) within a specific medium.
Mechanical waves can be either longitudinal or transverse.
Chapter 1: A
Define a medium
A medium (in the context of waves) is defined as any physical substance in which a wave can propagate through.
Chapter 1: B
Define a wave cycle
A wave cycle is defined as the process of a wave completing one full oscillation, with the wave ending up in a configuration identical to its initial configuration.
Chapter 1: B
Define the property of “amplitude.”
The amplitude of a wave refers to the maximum displacement of a particle (from a wave’s neutral point) which oscillates a wave.
Symbol A:
Chapter 1: B
Define the term “crest.”
The crest refers to the maximum positive displacement of a particle that oscillates a wave.
Chapter 1: B
Define the term “trough.”
The trough refers to the maximum negative displacement of a particle that oscillates a wave.
Chapter 1: B
Define the property of “wavelength.”
This term refers to the distance covered (in meters) of one complete wave cycle.
Symbol-L shaped
Chapter 1: B
Define the property “frequency.”
The frequency of a wave refers to the number of wave cycles completed per unit of time.
Expressed in HZ.
Symbol-F
Chapter 1: B
Define the property of “period.”
The period of a wave refers to the time taken (in seconds) to complete one full wave cycle.
Symbol-T
Chapter 1: B
Distinguish between a displacement/distance graph and a displacement/time graph.
A displacement/distance graph pauses a wave at a particular point in time. It can be used to dictate the amplitude and wavelength of a wave.
A displacement/time graph observes the movement of a certain particle oscillating a wave over time. It can be used to dictate the amplitude, period, and frequency of a wave.
Chapter 1: B
Describe how the source of a wave impacts its frequency and period.
The source of a wave refers to the matter or particles oscillating in that wave.
The faster the particles or matter oscillate of a wave, the greater the corresponding frequency will be. Due to the inverse relationship, a higher frequency will yield a lower period for that wave.
Chapter 1:c
Define the electromagnetic spectrum
The Electromagnetic spectrum (EM) comprises all the varying forms of electromagnetic radiation based on their frequencies and wavelengths.
The spectrum is ordered by increasing frequencies (and energies) and decreasing wavelengths.
Chapter 1:c
List the order of the EM spectrum.
Radio waves-
Microwaves-
Infrared-
Visible light-
Ultraviolet-
X rays-
Gamma rays-
Chapter 1:c
List the proportions of EM regions emitted via the sun
The sun emits the following proportions of electromagnetic radiation.
50% infrared-40% visible light-10% Ultraviolet
Chapter 1:c
List the frequencies of the visible spectrum in order of decreasing wavelengths.
Red-Orange-Yellow-Green-Blue-Indigo-Violate.
Chapter 1:c
Describe the use of Radio waves in society
Given Radio waves have the longest wavelengths across all regions on the EM spectrum these rays can travel long and uninterrupted distances, diffracting around large objects.
This form of EM radiation is used commonly in communication settings. As radio waves are emitted via towers and can be picked up by antennas.
Chapter 1:c
Describe the use of micro-waves in society
Given microwaves also comprise significant wavelengths with shorter frequencies they are utilized in society regarding radar/WiFi systems and phone signals, as these rays can travel long distances. Microwaves can also be used to heat food as well.
Chapter 1:c
Describe the use of infrared rays in society
All objects with a temperature greater than 0 K will emit infrared radiation due to the kinetic energy of particles.
Infrared is used in various activities that involve heat/heat transmissions. Including radiation heaters which convert infrared radiation to different objects in an area, causing them to heat up.
Chapter 1:c
Describe the use of visible light in society.
Visible light allows humans to perceive color. When a human sees a color it’s a frequency of the visible spectrum, being reflected off an object with the remaining frequencies absorbed by that object.
