THE ELECTROMAGNETIC SPECTRUM Flashcards
what are electromagnetic waves?
they’re electric and magnetic disturbances that can be used to transfer energy from a source to an absorber
microwave ovens -
energy is transferred from a microwave source to the food in the oven, heating it
radiant heaters -
infrared radiation transfers energy from the heater to heat the surroundings
the energy electromagnetic waves transfer depends on the
wavelength of the waves
what do waves of different wavelengths have?
they have different effects
long-wave radio waves have wavelengths as longs as
10 km
x-rays and gamma rays have wavelengths as short as
10^-15 m ( 10 to the power of -15 metres )
what do your eyes detect?
visible light, which is only a limited part of the electromagnetic spectrum (wavelengths of visible light ranges from just below 400 nm to above 700 nm)
what is the speed electromagnetic waves travel at, through space or in a vacuum?
300 million m/s = 3.0 x 10^8
the shorter the wavelength of the waves =
the higher their frequency
when does the energy of the waves increase?
when the frequency increases
as the wavelength decreases along the electromagnetic spectrum from radio waves to gamma rays
the energy and the frequency of the waves increase
what happens when an atom/nucleus emits electromagnetic waves?
it emits a packet of waves called a photon
- its energy is proportional to the frequency of the emitted waves
- the bigger the frequency of emitted radiation, the greater the energy of each photon
what is the spectrum?
it’s continuous
why are the frequencies and wavelengths at the boundaries approximate?
the different parts of the spectrum are not precisely defined
