Stopping Potential and kinetic potential

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    Kinetic Potential
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Stopping potential refers to the voltage difference between the emitter and collector in an electron emission setup, typically resulting in a positive value. The equation for maximum kinetic energy, expressed as max kinetic_energy = e * Vs, indicates that 'e' represents the elementary charge, approximately +1.602 x 10^-19 coulombs. When calculating kinetic energy with a positive stopping potential, the result will also be positive, confirming the energy's nature. The discussion highlights that using the electron charge requires considering the negative direction, affecting the voltage sign. Clarity in units and definitions is essential for accurate calculations in these contexts.
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[URGENT! Stopping Potential~~~~~~~#######~~~~~~~~~~~~~~~~

Homework Statement



max Kinetic_energy= e*Vs=hf-work_function

Vs is the stopping potential


The attempt at a solution

I am wondering, does this stopping potential refers the voltage difference of
V_Emitter (where the line shines on) - V_collector(where the electron travels to), and thus, the stopping potential is usually positive?

Also, for that equation max kinetic_energy= e*Vs, 'e' is just the charge= +ve 1.602*10^-19?
so that the max kinetic energy in this case, (+5 V)*(+ 1.602*10^-19)= +ve number?
 

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I am wondering, does this stopping potential refers the voltage difference of
V_Emitter (where the line shines on) - V_collector(where the electron travels to), and thus, the stopping potential is usually positive?
If you use e as elementary charge, it has to be positive.
If you use the electron charge, you need the opposite direction, and a negative voltage. That is just a matter of definition.
so that the max kinetic energy in this case, (+5 V)*(+ 1.602*10^-19)= +ve number?
What do you mean with "+ve number"? If you add units, you will get the right result.
 
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