3.2 keywords - wave-particle duality

Newton’s corpuscular theory

Light consists of particles called corpuscles

Huygen’s wave theory

light was a wave and at every point on a wavefront is a point source to secondary wavelets which spread to form the next wave

Maxwell prediction

EM waves existed and theorised a formula for their speed in a vacuum

black body

absorbs and emits all possible wavelengths of radiation

Wave theory

As wavelength of radiation decreases, the intensity of radiation would increase, leading to a predicting infinite amount of UV radiation being emitted - this lead to the UV catastrophe

Stopping potential

The work needed to be done by photoelectrons against the electrostatic force of attraction

Planck’s interpretation of EM waves

EM waves travel in discrete packets called quanta, which have an energy directly proportional to their frequency

Resolving power of a microscope

It’s ability to distinguish structures which are close to each other

Transmission electron microscope (TEM)

A type of electron microscope that uses and electron gun to produce electrons by thermionic emission and uses their reflection to scan a surface

Scanning tunnelling microscope (STM)

A type of electron microscope that uses a fine-tipped metal probe to scan the surface at a height around 1 nm

De Broglie hypothesis

States all particles have a wave-like nature and a particle nature