Where does an electron's kinetic energy go?

AI Thread Summary
When electrons move through a wire, their potential energy is converted into kinetic energy, which can be transformed into heat due to interactions with other electrons and the wire's crystal structure. The drift velocity of electrons is low, but their random velocities can be significant. The discussion highlights skepticism about the role of kinetic energy in powering a circuit, suggesting that the energy delivered is primarily from electrons moving between potential differences. The analogy of comparing electron kinetic energy to weights in a grandfather clock emphasizes that while electrons do move, their kinetic energy is not the main source of power in a circuit. Overall, the conversation underscores the complexity of energy transformation in electrical systems.
LightningB0LT
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When an electron moves through a wire between two terminals on a battery some of its potential energy is converted to kinetic energy. My question is, where does that kinetic energy go once it reaches the other terminal? Some of it is probably converted to heat, but what about the rest of it?
 
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hw about in the chemical bond that it makes when its attached to an atom?
 
Electrons are very light and move at a rather slow velocity. Their kinetic energy is completely negligible unless your application is a particle accelerator.
 
mrspeedybob said:
Electrons are very light and move at a rather slow velocity. Their kinetic energy is completely negligible unless your application is a particle accelerator.

Absolutely incorrect. In a room temperature conductor electrons have random velocities which are a significant fraction of c. What is low is the DRIFT velocity imposed but the EMF of a circuit.

Some Kinetic energy is converted to heat due to interactions with other electrons and the crystal structure.
 
Yes. I was referring to drift velocity. Thank you for the correction.

I am dubious however about the contribution of kinetic energy to the energy delivered by the circuit, including the energy converted to heat. The energy delivered by the circuit is the energy of electrons moving from higher potential to lower potential.

Talking about the kinetic energy of electrons in a circuit seems to me like talking about the kinetic energy of the weights that power a grandfather clock. Yes, they do move but it's a stretch to say the clock is powered by their kinetic energy.
 
I was using the Smith chart to determine the input impedance of a transmission line that has a reflection from the load. One can do this if one knows the characteristic impedance Zo, the degree of mismatch of the load ZL and the length of the transmission line in wavelengths. However, my question is: Consider the input impedance of a wave which appears back at the source after reflection from the load and has traveled for some fraction of a wavelength. The impedance of this wave as it...
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