Science WEEK 1-2 Flashcards
disturbance in space
Waves
highest point in a wave
Crest
lowest point in a wave
Trough
distance from midpoint to highest or lowest parts of a wave
Amplitude
distance between two successive identical parts of a wave
Wavelength
number of waves produced in one second or a full wavelength
Frequency
extent of limits between which variation is possible
Range
wave that oscillates matter and transfers energy through a medium (up and down movement of wave)
Mechanical wave
particle motion is perpendicular to wave motion
Transverse
particle motion is in the same direction as wave motion
Longitudinal
are transverse (doesn’t need a medium) and is formed
when an electric field comes into contact with a magnetic field
– disturbance that moves through space at the speed of light
Electromagnetic wave
created by charged particles (could be horizontal)
Electric field
produced by moving electric changes (could be
transverse)
Magnetic field
Scottish physicist who predicted the existence of electromagnetic waves in
1862
James clerk maxwell
German physicist who backed Maxwell’s theory by demonstrating the existence
of waves other than light in 1887
Heinrich Hertz
is a continuous range of electromagnetic waves arranged in order of frequency
or wavelength
Electromagnetic Spectrum
An Italian inventor who, in 1901, sent and received the first transatlantic
wireless message
– Awarded the Nobel Prize along with Karl Ferdinand Braun for their work on the
development of wireless telegraphy
Guglielmo Marconi
– Have the longest wavelengths (104m - 10-1m) and shortest frequencies
(30kHz to 3000 MHz)
– Most suitably usable in communication devices across all platforms
– Frequency can range between 3 kiloHertz to 300 GigaHer
Radio Waves
– used for various purposes, including detecting objects, weather forecasting,
military surveillance, air traffic control, monitoring speed in highway patrol, and
tracking satellites and debris
Radar
– Have longer wavelengths (180-550 meters)
– Radio stations modulate or change the amplitude of the radio waves they
transmit by incorporating audio information, known as the input or
modulating signal
– Characterized by MF (Medium Frequency).
Amplitude modulation
– Short radio waves (2.8-3.4 meters)
– Radio stations modulate the frequency of the carrier signal
– Considered a region of VHF (Very High Frequency), such as the TV band
(54 to 890 MHz)
– amplitude and other parameters of the resulting signal remain constant,
as seen in the CP (UHF) Ultra High Frequency band
Frequency Modulation
– part of the electromagnetic spectrum located between radio waves and infrared
light.
– are called microwaves because their wavelengths are much shorter than those
of radio waves.
– James Clerk Maxwell discovered microwaves
Microwaves
– lies between the microwave region and the lower frequency edge of the visible
spectrum
– Discovered by Sir William Hershel in 1800
– longer than visible light and include most thermal radiation emitted by objects
at room temperature
– Used for remotely determining the temperature of objects through techniques
like thermography or pyrometry
Infra red radiation
Closest in wavelength to visible light; commonly used
in devices like remote controls
Near infrared light
Closer to the microwave region in the electromagnetic
spectrum; examples include sunlight, fire, or a radiator
Far infrared
– The portion of electromagnetic radiation detectable by the human eye.
– It occupies a small segment of the electromagnetic spectrum.
– When all the colors are combined, they create white light.
Visible light
longest wavelength; shortest frequency and is the most energetic
Red
shortest wavelength; longest frequency and the least energy
Violet
– Has a wavelength shorter than visible light but longer than X-rays
– The term literally means “above violet”
– UV light is produced by high-temperature surfaces
– Discovered by Johann Wilhelm Ritter, a German chemist and physicist
Ultraviolet
– are high-energy waves with great penetrating power
– widely used in imaging and diagnostics
– Discovered by Wilhelm Conrad Roentgen in 1895, they revolutionized medical
technology by allowing non-invasive views of internal body structures
X-rays
– generated by radioactive atoms and during nuclear explosions.
– treatment of certain types of cancer, such as in Gamma Knife Surgery
– Paul Villard was a French chemist and physicist who discovered gamma rays in 1900
Gamma rays
