Solve Change in Voltage: Why is V=ED?

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SUMMARY

The change in voltage between two capacitor plates is defined as V=ED, where E represents the electric field strength and D denotes the displacement between the plates. This relationship contrasts with the equation V=-ED, which describes the potential change in the direction of the electric field. The confusion arises from differing definitions of voltage, where some refer to it as electric potential while others define it as potential drop. According to Ohm's Law, the current I through a resistor causes a voltage drop V=IR, which is distinct from the behavior observed in capacitors.

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Homework Statement


Why is the change in voltage between two capacitors V=ED ?

Homework Equations


V=-ED

The Attempt at a Solution


Isn't the change in voltage equal to the negative of the product of the electric field and displacement?
So, why is it that for a capacitor the change in voltage is not V=-ED ?

Thanks for any help.
 
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The flow of electrons through a capacitor is directly proportional to the rate of change of voltage across the capacitor, but in the case of resistors it is directly proportional to the voltage drop.. from there it appears the difference.. at least that's what I think :)
 
There is some confusion when speaking about voltage. Some people call the electric potential "voltage" others define voltage as potential drop. According to Ohm's law, the current I causes a potential drop - voltage- across a resistor R, equal to V= IR, but the electic potential changes by -IR in the direction of the current.
Between the capacitor plates, the potential U changes by -ED in the direction of the electric field, that is from the + plate to the - one, and by + ED in the opposite direction. Or you can say that the potential of the positive plate is by ED volts higher than the potential of the negative plate.

ehild
 

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