Planck’s idea that energy exchange and radiation happens in packets of energy.
Planck said that the photoelectric effect helped him.

Bohr Frequency Condition:
E = Energy magnitude OR change in energy (Joules)
v = frequency (nu) (Hz)
h = Planck’s Constant = 6.629e-34 J s

The Photoelectric Effect:
Electrons are ejected from metals if hit by UV radiation.

A packet of energy
Red light is actually just a stream of low energy photons

The Work Equation:
If the energy is less than what is required, then it won’t eject
This means that at higher frequencies, the number of electrons, doesn’t change, but the kinetic energy does.

Basically cutting up waves, so they deflect weirdly.
Proves the light behaves like a wave.

Constructive Interference:
Increased amplitude of waves
(Added on top of each other)

Destructive Interference:
Decreased amplitude of waves
(Taken the average of)

De Broglie Relation:
A “matter” wave, will also have mass, so this:
v = Speed (m/s)
m = Mass (kg)
Linear Momentum (p) = m*v

Heisenberg Uncertainty Principle:
This says that the uncertainty of the momentum and position of a particle can’t go higher than some constant, which means, if one uncertainty is big, then the other one must be small.
So you know 90% of the momentum, then you know 10% of the position.