Quantum Physics Flashcards
How does electromagnetic radiation travel through space?
as a continuous wave
How does electromagnetic interact with matter?
as a discrete energy quanta called photons
What is the definition of an electron volt?
the energy transferred when an electron travels through a potential difference of 1 volt
How many joules in 1 electron volt?
1.6 x 10^-19J
What does diffraction and superposition of light rely on?
radiation acting as a wave
How does radiation act as a wave?
wave particle duality
What is the relationship between wavelength associated with particles and momentum
inversely proportional
How can electrons be made to diffract?
when fired as a beam at a thin piece of polycrystalline graphite
How do electrons act after being fired to diffract?
they are diffracted by gaps between the atoms and produce a diffraction pattern when they hit the screen
What is the photoelectric effect?
when electromagnetic radiation is shone onto a metal electrons are released from the surface
What is the set up of a gold leaf electroscope?
zinc plate on top of a negatively charged stem with a piece of gold leaf attached to the stem
What is initially the same between the gold leaf and the stem so that they repel eachother?
the charge
What causes electrons to be released from the plate?
shining UV light
What must each electron have at least in order to be released?
work function
Why does visible light not release electrons?
frequency is too low
