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Changing a Capacitor

Part of the Electricity and Magnetism section of Coddy's Physics journey. Lesson 19 of 51.

A dielectric between the plates multiplies the capacitance by κ:

C = κ ε₀ A / d

A capacitor with a dielectric

Still connected to the battery: V stays the same. Disconnected: Q stays the same. Then use Q = C V with the new C.

Challenge

A 2 μF capacitor is charged to 50 V and disconnected. Its plates are then pulled apart to twice the distance. What is its voltage V_2 now?

Try it yourself

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

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4Charged Conductors

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7Real Batteries

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10Magnetic Fields

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2The Electric Field

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5Capacitors

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8Kirchhoff's Laws

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11Magnetic Forces

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3Energy and Potential

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6Current and Resistance

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9Capacitors in Circuits

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12Induction

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