Wave-particle duality Flashcards
How is light wave-like?
it diffracts when light passes throigh a narrow slit
the light spreads out the same as water waves
How is light particle like?
the photoelectric effect
when light is directed at a metal surface an electron absorbs a photon
What is the evidence for electrons being particles?
they can be deflected by a ELECTROmagnetic field
What was de Broglie’s hypothesis?
matter particles have a dual wave-particle nature
the wave like behaviour of a matter particle is characterised by a wavelength, the de Broglie wavelength
which is related to momentum
What is the de Broglie wavelength equation?
λ = h / p = h / mv
What is the evidence for de Broglioe’s hypothesis?
it was discovered that electrons can be diffracted
How were these electrons diffracted?
narrow beam of electrons in a vacuum tube is directed at metal foil, the rows of atoms in the foil cause electrons to be diffracted
directed at a fluorescent screen and forms rings
electrons are attracted to a heated filasment wire to a positively charged metal plate with a small hole in the centre
