Photoelectric Effect Flashcards
Support of the Ray model of light
A bean of light can be seen from a laser/ray box as a ray can be observed to REFLECT OR REFRACT as a ray
what are the properties of a light WAVE
Light can be seen to have wave properties it refracts reflects and diffracts
Particle model of light (corpuscle model)
Light behaved as a particle (a photon)
What experiment demonstrated light having particle properties
Golden leaf experiment
What factors effect the release of electrons
Frequency - higher the faster the electron
Power(intensity)- higher increases electrons release per second
Einstein’s explanation of photons(interaction of photons and what their energy depends on)
Light composed of photons of energy in a fixed amount that depended on it frequency 1:1 interaction of photons and electrons
Define intensity of light
Intensity of light source is proportional to the number of photons emitted per second
Define electron volt
An eV is the work done moving one electron through a PD of 1V
1eV = 1.60x10^-19
Define work function
The minimum energy of a photon required to release release one electron from the surface of a metal
Photon energy equation
E= hf = hc/λ
Photoelectric effect equasion
hf = φ +Ek(max)
Threshold frequency
Minimum frequency of radiation required to cause an electron to be emitted
hfο=φ
(no kinetic energy as particle is only just realeased)
Threshold wavelength
Wave length must be below the threshold wavelength to emit an electron
hc/λo =φ
Stopping potential experiment
Millikan disagreed and did a peer review of photon theory
Measured the stopping potential of electrons emoted from the same metal at different frequencies using a photocell
