1.1 electromagnetic radiation Flashcards
how is the energy of one mole of photons given?
E = lhf or E = lhc/λ
how can the energy of one photon be given?
E=hf or E=hc/λ
what is the relationship between the frequency of the photon and the energy transferred?
increased frequency = increased energy
what happens when a photon is absorbed or emitted?
energy is gained or lost by electrons within the substance
a photon carries quantised energy proportional to…
the frequency of radiation
how does electromagnetic radiation behave when it absorbed or emitted by matter?
as a stream of particles, known as a photon
why is electromagnetic radiation said to have a dual nature?
it be described as both a wave and a particle
what is the relationship between speed, frequency and wavelength given by?
c = fλ
what is frequency?
number of waves that pass a fixed point in one unit of time
which units are used to measure frequency?
m-1 or Hz
what is velocity?
rate or change of displacement of an object
which unit is used to measure velocity?
ms-1
which unit is used to measure wavelength?
metres or nanometres
where does the visible region span from?
the red end to the violent end
how does energy change as wavelength decreases?
it increases
