waves interim Flashcards
(29 cards)
electromagnetic radiation
waves of energy produced by changing electric and magnetic fields
electromagnetic spectrum
the arrangement of electromagnetic waves according to wavelength
wave
a repeating disturbance of movement that transfers energy through matter or space, waves are caused by vibrations
medium
the matter through which a wave travels
transverse wave
a wave in which matter in the medium moves back and forth at a right angle to the direction the wave travels
compressional wave
a wave in which the matter in the medium moves back and forth in the same direction that the wave travels
crest
the high point of a transverse wave
trough
the low point of a transverse wave
wavelength
the distance between two crests or troughs on a wave
frequency
the number of waves that pass through a given point per second
period
the amount of time it takes one wavelength to pass a fixed point
amplitude
the measure of the energy that a wave carries
velocity =
frequency * wavelength
speed of light
300,000 km/second
light year
the distance that light travels in one year - 9.46 trillion km
astronomical unit
the average distance between the earth and the sun - 150 million km
why are special units needed to measure distances in space?
because space is so huge, it would be impractical to use normal units
the arrangement of electromagnetic waves according to wavelength is called…
the electromagnetic spectrum
which part of the electromagnetic spectrum do human eyes detect?
visible light spectrum
colors result from the fact that each color of light has a different…
wavelength
relationship between frequency and wavelength:
the higher the frequency, the shorter the wavelength.
the longer the wavelength, the lower the frequency.
which wavelengths carry the most energy? (length and color)
shorter, blue
how is amplitude measured?
finding the distance between the crest/trough and rest position. the taller the wave, the greater the energy/amplitude
x-rays
used to make images of the body
