How Does Voltage Drop Across a Resistor?

AI Thread Summary
Voltage drops across a resistor due to the resistance encountered by moving charges, primarily electrons, which lose potential energy in the process. This loss of potential energy is converted into heat, which is why resistors dissipate power. The relationship between current and voltage drop can be expressed with the formula Power = I ΔV, indicating that the energy lost is proportional to the current and the voltage difference. The discussion emphasizes that while positive charges are less mobile, the movement of electrons filling "holes" is what primarily contributes to the voltage drop. Ultimately, the concept of voltage is not about a physical entity moving but rather a change in energy state as charges pass through the resistor.
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Hello,

I am having conceptual difficulties trying to understand how voltage is dropped across a resistor. The whole idea of it is confusing to me, where does this voltage go?

Could it be explained in terms of point charges and electric fields, which is how I am able to visualize potential difference.

The way I see it, the positive charges move across a resistor and face some sort of resistance to their motion, but how does that relate to the charges losing potential?
 
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where does this voltage go?
Voltage is not a material, it does not "go" somewhere.
Where does the height of a ladder (not your height!) "go" if you climb it down?

The way I see it, the positive charges move across a resistor and face some sort of resistance to their motion, but how does that relate to the charges losing potential?
They need some energy to cross the resistor. Moving positive charges are quite rare.
 
where does this voltage go

Think of it in terms of power.

Power = I ΔV.

It escapes as heat.
 
positive charges don't move as much as the electrons move to fill "electron holes"
 
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