Does the capacitance change as voltage increases in a circuit?

AI Thread Summary
As voltage increases in a circuit, the capacitance remains unchanged because it is determined by the physical characteristics of the capacitor, specifically the area of the plates and the distance between them. The relationship between charge (Q) and voltage (V) is direct, but this does not affect capacitance, which is a constant for a given capacitor. The formula C = (epsilon_0 * A) / d supports this, indicating that capacitance is independent of voltage as long as the breakdown voltage is not reached. Therefore, the correct conclusion is that capacitance does not change with increasing voltage. This understanding is crucial for analyzing capacitor behavior in electrical circuits.
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Homework Statement



As the voltage in the circuit shown below is increased (but not to the breakdown voltage), the capacitance

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a. increases.

b. decreases.

c. does not change.

d. increases, decreases, or does not change, depending on the charge on the plates of the capacitor.

e. does none of these.


Homework Equations



C = Q/V or C = (epsilon_0*A)/(d)

The Attempt at a Solution



If the voltage increases at a specific rate, then the charge would also increase since Q and V are directly proportional and the ratio between the two is a constant. Therefore, the capacitance does not change?

Thanks.
 
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The capacitance should remain the same as it is a function of geometry and the material between the plates.

C = (epsilon * A) /d
 
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