Photoelectric Emission Process

The photoelectric emission process refers to the phenomenon where electrons are emitted from a metal surface when it is exposed to light or electromagnetic radiation. This process can be explained using the concept of the photoelectric effect.

Work Function

The work function is the minimum amount of energy required to remove an electron from the surface of a metal. It is denoted by the symbol Φ and is measured in electron volts (eV). In this case, the work function of the metal is given as 1.8 eV.

Kinetic Energy of Most Energetic Electrons

The kinetic energy of the most energetic electrons can be calculated using the formula:

Kinetic Energy = Energy of Incident Photon - Work Function

In this case, the kinetic energy is given as 0.5 eV. Therefore, we can rewrite the formula as:

0.5 eV = Energy of Incident Photon - 1.8 eV

Solving for the energy of the incident photon:

Energy of Incident Photon = 0.5 eV + 1.8 eV = 2.3 eV

This means that the energy of the incident photon is 2.3 eV.

Stopping Potential

The stopping potential refers to the minimum potential difference required to stop the most energetic electrons from reaching the anode. It can be calculated using the formula:

Stopping Potential = Energy of Incident Photon - Kinetic Energy of Electrons

In this case, the energy of the incident photon is 2.3 eV and the kinetic energy of the electrons is 0.5 eV. Therefore, we can substitute these values into the formula:

Stopping Potential = 2.3 eV - 0.5 eV = 1.8 eV

So, the stopping potential in this case is 1.8 eV.

Explanation

When light or electromagnetic radiation falls on the metal surface, it transfers its energy to the electrons present in the metal. If the energy of the incident photon is greater than or equal to the work function of the metal, electrons are emitted from the surface.

The most energetic electrons are the ones that require the least amount of energy to be emitted. In this case, their kinetic energy is given as 0.5 eV. By using the formula mentioned above, we can calculate the energy of the incident photon, which is found to be 2.3 eV.

The stopping potential is the potential difference required to stop the most energetic electrons from reaching the anode. It can be calculated by subtracting the kinetic energy of the electrons from the energy of the incident photon. In this case, the stopping potential is found to be 1.8 eV.

This means that a potential difference of 1.8 eV is required to stop the most energetic electrons from reaching the anode.