Why would voltage stay the same when a dielectric is introduced?

AI Thread Summary
The introduction of a dielectric increases the capacitance of a capacitor, which is inversely related to voltage according to the equation Q=CV. However, when a dielectric is added, it affects all capacitors in the circuit, leading to a situation where the voltage across capacitor 3 remains constant. This is because the overall charge distribution and potential difference are maintained in the circuit. The dielectric's effect is uniform across the capacitors, ensuring that voltage does not decrease as initially expected. Understanding this relationship clarifies how dielectrics influence capacitance and voltage in a circuit.
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I need an explanation for question 6. Why would voltage stay the same across capacitor 3?


The dielectric increases capacitance which is inversely related to voltage correct? The equation Q=CV says this. So shouldn't voltage decrease across capacitor 3?
 
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How do you get the voltage of C3 in the original set-up? How does the dielectric change all capacitance?

ehild
 
Yes the capacitance does increase but it does so for all three capacitors.Take another look at the question.


Hello ehild.You just beat me to it.
 

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