Calculating electrons emitted question.

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In summary, the question is asking for the number of electrons emitted from the cathode per second, and the solution involves calculating the energy of a photon and the number of photons striking the cathode each second. The equation for this problem is unknown and the proposed solution involves dividing the number of photons by the charge of an electron. The current between the cathode and anode may also be relevant in finding the answer.
  • #1
ConfusedElect
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Hi all, I realize the subsequent question is likely to be quite simplistic; therefore I apologise in advance and I hope I am not offending fellow users. Here’s the question: “How many electrons are emitted from the cathode each second?”
How would I go about answering this question?

I have previous calculated the energy of a photon and the number of photons striking the cathode each second.

Thank you in advance for any help provided :)
CE
 
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  • #2

Homework Statement


Here’s the question: “How many electrons are emitted from the cathode each second?”
How would I go about answering this question?
I have calculated the energy of a photo using E=hf and I also have calculated the number of photons striking the cathode each second.



Homework Equations


I am not sure of the equation for this problem as I am unable to locate it in my current Physics literature/I have also been unable to locate a relevant equation on the internet.


The Attempt at a Solution


Would I divide the number of photons striking the metal per second by the charge of an electron? Therefore: (number of photons striking cathode each second)/1.6*10-19...

The numebr I obtain doesn't seem very realistic ;\.

Thank you :).
CE
 
  • #3
Do you know the current between the cathode and anode?
 
  • #4
(two threads merged)
 
  • #5
G01 said:
Do you know the current between the cathode and anode?

Thank you very much :)!
CE
 

1. How do you calculate the number of electrons emitted in a given situation?

To calculate the number of electrons emitted, you will need to know the intensity of the electric or magnetic field, the surface area of the emitter, and the work function of the material. The equation used is: number of electrons emitted = intensity of the field * surface area * work function.

2. What is the work function and how does it affect the number of electrons emitted?

The work function is the minimum amount of energy required to remove an electron from the surface of a material. It is directly related to the number of electrons emitted, as a higher work function means more energy is needed to release electrons, resulting in a lower number of emitted electrons.

3. Can the number of electrons emitted be manipulated by changing the material of the emitter?

Yes, the number of electrons emitted can be affected by the material of the emitter. Different materials have different work functions, and therefore, a material with a lower work function will emit more electrons than a material with a higher work function.

4. Are there any other factors that can influence the number of electrons emitted?

Yes, there are other factors that can affect the number of electrons emitted. These include the temperature of the emitter, the angle of the electric or magnetic field, and the presence of any external sources of light or radiation.

5. How is the number of electrons emitted related to the current in a circuit?

The number of electrons emitted is directly related to the current in a circuit. As more electrons are emitted, the current in the circuit increases. This is because electrons carry charge, and a larger number of electrons means a larger flow of charge, resulting in a higher current.

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