Can I Convert Volts to Electron Volts in Photoelectric Effect Calculations?

  • Thread starter prehisto
  • Start date
  • Tags
    Units
In summary, the photoelectric effect problem involves calculating the incident light frequency given an electric potential of 3V and the work function. The equation used is Emax = hfinc - φ and the units are [V] = [J] - [J]. However, converting from [V] to [eV] by multiplying V by e may be incorrect as V is not a measurement of energy. Instead, the relationship between electric potential and energy of a charge in a field needs to be found.
  • #1
prehisto
115
0

Homework Statement


HI, I have this photoelectric effect problem, it is not so difficult but when i got to the units and red about it , i got confused.
The Problem : Photo-electrons are completely hold up by electric potential with potential of 3V. The work function is given. I have to calculate the incident light frequency.

Homework Equations

The Attempt at a Solution


So the equation is
Emax=hfinc

And the units are
[V]=[J]-[J]
This does not work. So I thought let's convert them to eV which is possible for [J].
But when I start to think about the V -> eV its gets confusing because V are not measurement of energy but eV are.

So what do you think guys, can I just do the conversion from [v] to [ev] by multiplying V by e or it is wrong?
 
Physics news on Phys.org
  • #2
Emax does not denote the stopping potential, but the kinetic energy of a photoelectron. You need to find the relationship between electric potential and energy of a charge in a field.
 

1. What is the photoelectric effect?

The photoelectric effect is the phenomenon where electrons are emitted from a metal surface when it is exposed to light of a certain frequency. This was first observed by Heinrich Hertz in 1887 and explained by Albert Einstein in 1905.

2. What is the unit of energy for the photoelectric effect?

The unit of energy for the photoelectric effect is the electron volt (eV). This is a unit of energy equal to the amount of energy gained by an electron when it is accelerated through a potential difference of one volt. It is a commonly used unit in atomic and nuclear physics.

3. How is the photoelectric effect related to the frequency of light?

The photoelectric effect is directly related to the frequency of light. According to Einstein's theory, the energy of a photon (a particle of light) is directly proportional to its frequency. Therefore, only light with a frequency above a certain threshold can cause the emission of electrons in the photoelectric effect.

4. What is the work function in the photoelectric effect?

The work function in the photoelectric effect refers to the minimum amount of energy required to remove an electron from the surface of a metal. It is different for different metals and is a key factor in determining the threshold frequency for the photoelectric effect.

5. How is the photoelectric effect used in modern technology?

The photoelectric effect has many practical applications in modern technology. Some examples include photovoltaic cells, which convert light energy into electrical energy, and photoelectric sensors, which use the photoelectric effect to detect and measure light. It is also used in certain types of imaging techniques, such as photoelectron spectroscopy, to study the electronic structure of materials.

Similar threads

  • Introductory Physics Homework Help
Replies
9
Views
839
  • Introductory Physics Homework Help
Replies
25
Views
2K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
2
Replies
35
Views
1K
  • Introductory Physics Homework Help
Replies
8
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
12
Views
728
Replies
1
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
1K
Back
Top