PERE'S LAW AND THE FREQUENCY OF ELECTRON BEAM IMPACTS ON METAL

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The discussion centers on calculating the frequency of electron impacts on a metal block given a current A. The relationship between current, charge, and time is established using the equation i=q/t, leading to the conclusion that frequency can be expressed as 1/t = A/e, where e is the elementary charge. Participants clarify that the number of electrons per unit time, or frequency, is derived by dividing the current by the charge of an electron. The consensus is that the calculation is correct, confirming the connection between current and electron frequency. Understanding this relationship is crucial for solving the problem effectively.
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Homework Statement


A beam of electrons is hitting a block of metal with current A. What is the frequency they are hitting the block?


Homework Equations


i=q/t


The Attempt at a Solution



i=q/t => 1/t=i/q. So then 1/t=A/e, where e is the elementary charge.
This may in fact be right. Our prof gave it to us as a question to think about and I want to know what everyone else is thinking.
 
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promiseskept said:

Homework Statement


A beam of electrons is hitting a block of metal with current A. What is the frequency they are hitting the block?


Homework Equations


i=q/t


The Attempt at a Solution



i=q/t => 1/t=i/q. So then 1/t=A/e, where e is the elementary charge.
This may in fact be right. Our prof gave it to us as a question to think about and I want to know what everyone else is thinking.
Let dn/dt = the number of electrons per unit time flowing (ie. the frequency at which electrons hit the block).

What is the current in terms of dn/dt?

AM
 
Andrew Mason said:
Let dn/dt = the number of electrons per unit time flowing (ie. the frequency at which electrons hit the block).

What is the current in terms of dn/dt?

AM

Wouldn't that just be like I said, the current divided by the charge, thus saying how many electrons per unit time. [A]/[C] * e=[C*s]/[C]=1/[C] * e = 1/ electrons.
 
promiseskept said:
Wouldn't that just be like I said, the current divided by the charge, thus saying how many electrons per unit time. [A]/[C] * e=[C*s]/[C]=1/[C] * e = 1/ electrons.
It was not clear what you meant by t or 1/t. The number of electrons per second is the Current (in coulombs/sec or Amperes) divided by the charge of one electron (in Coulombs). If that is what you meant by 1/t then you were correct.

AM
 
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