obtain emissions photoelectric equations with necessary explanation
Answers
Answer:
ANSWER
Einstein's photoelectric equation.
According to Einstein, the emission of photoelectron is the result of the interaction between a single photon of the incident radiation and an electron in the metal.
When a photon of energy hv is incident on a metal surface, its energy is used up in two ways.
(i) A part of the energy of the photon is used in extracting the electron from the surface of metal, since the electrons in the metal are bound to the nucleus. This energy W spent in releasing the photoelectron is known as photoelectric work function of the metal. The work function of a photo metal is defined as the minimum amount of energy required to liberate an electron from the metal surface.
(ii) The remaining energy of the photon is used to impart kinetic energy to the liberated electron. If m is the mass of an electron and v its velocity, then
Energy of the incident photon = Work function + Kinetic energy of the electron
hγ=W+
2
1
mv
2
....(1)
If the electron does not lose energy by internal collisions, as it escapes from the metal, the entire energy (h−W) will be exhibited as the kinetic energy of the electron Thus, (h−W) represents the maximum kinetic energy of the ejected photoelectron. If Vman is the maximum velocity with which the photoelectron can be ejected, then
hv=W+
2
1
mv
max
2
....(2)
This equation is known as Einstein's photoelectric equation.
When the frequency (γ) of the incident radiation is equal to the threshold frequency (γ
0
) of
Answer:
The photoelectric effect is a phenomenon in which electrons are ejected from the surface of a metal when light is incident on it. These ejected electrons are called photoelectrons. It is important to note that the emission of photoelectrons and the kinetic energy of the ejected photoelectrons is dependent on the frequency of the light that is incident on the metal’s surface. The process through which photoelectrons are ejected from the surface of the metal due to the action of light is commonly referred to as photoemission.
The photoelectric effect occurs because the electrons at the surface of the metal tend to absorb energy from the incident light and use it to overcome the attractive forces that bind them to the metallic nuclei. An illustration detailing the emission of photoelectrons as a result of the photoelectric effect is provided below.
Photoelectric Effect Formula
According to the Einstein explanation of the photoelectric effect is:
The energy of photon = energy needed to remove an electron + kinetic energy of the emitted electron
i.e. hν = W + E
Where,
h is Planck’s constant.
ν is the frequency of the incident photon.
W is a work function.
E is the maximum kinetic energy of ejected electrons: 1/2 mv².