31 Flashcards
What is a quantum of light called?
photon
In the formulaE=hf, what doesfstand for?
The frequency of electromagnetic oscillation
Does light travel from one place to another in a wavelike or a particle-like way?
wavelike
Does light interact with a detector in a wavelike or a particle-like way?
particlelike
When electrons are diffracted through a double slit, do they hit the screen in a wavelike way or in a particle-like way? Is the pattern of hits wavelike or particle-like?
Particle-like, wavelike
If a beam of red light and a beam of blue light have exactly the same energy, which beam contains the greater number of photons?
a beam of red light
A quantum of light is a _________.
smallest lump of light
In the equationE = hf, thehis _________.
a proportionality constant
When the frequency of a photon is doubled, the energy it carries _________.
doubles
What exactly is ejected in the photoelectric effect?
Electrons
Which are more successful in dislodging electrons from a metal surface: photons of violet light or photons of red light? Why?
Violet light is more successful because the higher energy of a violet photon interacts with a single electron and gives it enough energy to escape the metal.
When does light behave as a wave? When does it behave as a particle?
Light is emitted and detected as a particle and travels as a wave.
quantization
the idea that the natural world is granular rather than smoothly continuous.
quantum
Any elemental particle that makes up matter or carries energy
Energy of a quanta?
is E =hf
Wave-particle duality
Photon behaves as a particle when emitted by an atom or absorbed by film, ect. But it behaves as a wave traveling from a source to the place it is detected.
Who proved light was a wave?
young
Who said radiant energy was emitted in discrete bundles?
Planck, called quantum
Photoelectric effect
Proof that light is photons. The brighter and higher frequency of light on a photosensitive surface, the greater the velocity of ejected photons. The emission of electrons from a metal surface when light is shined on it.
Particles as waves
wavelength = h/momentum Every particle of matter is associated with a corresponding wave.
Uncertainty principle
states that plancks constant sets a limit on the accuracy of a measurement. It is not possible to measure exactly both the position and the momentum of a particle at the same time nor the energy and the time during which the particle has that energy.
