Chapter 28. Quantum Theory April 8 th , 2013. Quantum Theory. Two things are really different at the atomic and sub-atomic scale: Wave-particle duality Particles are waves, waves are particles Energies are not continuous but discrete. They vary by discrete increments called quanta
April 8th, 2013
Two things are really different at the atomic and sub-atomic scale:
Wc = eV
h ƒc = Wc
KEelectron = h ƒ - h ƒc = h ƒ - Wc
Photoelectric EffectNobel prizeAlbert Einstein 1921
(his discovery was in 1905)
KEelectron = h ƒ - h ƒc = h ƒ– Wc
With his explanation of the photoelectric effect, Einstein introduced the idea that
light is made of particles, now called photons,and that their energies are quantized.
We now say that:
a photon is a quantum of light
An electron and a neutron have the same wavelength. What is the ration of (a) their kinetic energies and (b) their momenta? Assume the speeds are low enough that you can ignore relativity.