5.5: Capacitance and Dielectrics
- Page ID
- 32772
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Now that you have developed an understanding of electric fields and electric potentials, you have the tools needed to understand a capacitor. A parallel-plate capacitor consists of two conducting sheets close enough together so that they can store equal and opposite charge with a potential difference between them. The amount of charge a parallel-plate capacitor stores at a particular voltage depends on its geometry and is characterized as its capacity or capacitance (measured in farads \(= 1\) coulomb/volt). A common way to increase the capacitance of a capacitor is to put a dielectric (non-conductor) between the conducting plates. The charges in the dielectric are bound charges (not free to move away from a particular site within the material) in comparison with the free electrons of a conductor (that move in the presence of an electric field).