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| Parallel Plate Capacitors |
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| This capacitor is the most common type, which is cheapest and simplest to construct. |
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| It consists of two conducting plates parallel to each other and separated by a distance 'd', which is small when compared to the length of the plates. Practically the electric field is located between the two plates. There is a slight fringing of the field at its outer boundary. However, the fringing becomes less when the plates are brought more closer. There is a point when the fringing become neglected and field between the two plates are regarded to be uniform. |
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| If there is vacuum between the two plates, then it can be proved that the electric intensity between two closely spaced parallel plates is given by |
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| where 's' is the surface density of charge on either plate. If 'A' is the area of each plate and 'Q' is the charge on either plate, then |
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| As the electric intensity is uniform between the plates, the potential difference is given by |
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| V = Ed |
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| where 'd' is the separation between two plates. |
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| The capacitance of a parallel plate capacitor in vacuum is given as |
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| "Capacitance of a parallel plate capacitor is directly proportional to the area and inversely proportional to their separation. Hence capacitance does not depend on the charge". |
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