physics ch13

quantum

what is a photon

a fundamental particle which makes up all forms of electromagnetic radiation - defined as a massless ‘packet’ or a ‘quantum’ of electromagnetic energy

what is the formula for photon energy?

E = hf

where E = energy in J

f = frequency of electromagnetic radiation

h = Plancks constant (6.63 ×10^-34)

how is energy of a photon related to its frequency

they are directly proportional (as E= hf where h is constant)

What is the formula for photon energy using the photons wavelength?

E = (hc)/ λ

where c = speed of light

λ = wavelength

what is the relation between photon energy and frequency

E is inversley proprtional to λ as shorter λ = higher frequency = more energy

what is the quantum model

EM radiation has a particulate nature - tiny packets of energy rather than a continuous wave - called the ‘photon’

what are electron volts (eV)

the work done when one electron is moved through a potential difference of 1V

What is the equation relating energy and eV

E = eV x 1.6×10^-34