Photoelectric effect basics Flashcards
When ultraviolet (UV) radiation is
incident on the zinc plate, the gold leaf begins to fall. This phenomenon
is known as
The Photoelectric effect
If the intensity of the radiation is increased what happens to the number of electrons emitted per second?
The number of electrons emitted per second also increase
No matter the intensity, upon exposure to electromagnetic radiation, electrons are
emitted immediately from the surface of the metal
Minimum frequency required for electrons to be emitted from incident radiation
Threshold frequency (fo)
If the frequency of the incident radiation is greater than the minimum
frequency required for electron emission what happens to the maximum kinetic energy?
The maximum kinetic energy of emitted electrons increases
Electrons are emitted with a range of kinetic energies. The kinetic
energies range from…
zero to a maximum
What is a photon?
a quantum of
electromagnetic radiation.
WHo discovered the photoelectric effect?
Heinrich Hertz
Who further explained the photoelectric effect using a particle model rather than a wave model?
Albert Einstein
Value of planck’s constant
(6.63 × 10^−34 Js)
Energy of an incident photon equation
E = hf
energy needed to free electron from surface is also known as
The work function
Equation relating the work function to the energy of an incident photon
hf = φ + Ekmax
intensity of the incident electromagnetic radiation is defined as …
thepower incident per unit area on the surface.
Equation for intensity of incident electromagnetic radiation
I = P / A
Unit of intensity
W / m^2
Increasing the intensity of the incident
radiation causes what to happen to the number of incident photons?
An increase in the number of incident photons meaning more emitted electrons
Define cut off wavelength
the maximum wavelength of the
incident electromagnetic radiation
required for electrons to be emitted.
equation for work function(long equation)
φ = hfo = hc / λ0
constant used as a divisor to convert from Joules to electronvolts
1.6 × 10−19C ( ELEMENTARY CHARGE )
