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capacitor

INTRODUCTION :


The capacitor is a component which has the ability or “capacity” to store energy in the form of an electrical charge producing a potential difference (Static Voltage) across its plates, much like a small rechargeable battery.

CAPACITANCE :


Capacitance is the electrical property of a capacitor and is the measure of a capacitors ability to store an electrical charge onto its two plates with the unit of capacitance being the FARD (abbreviated to F) named after the British physicist Michael Faraday.



Capacitance is defined as being that a capacitor has the capacitance of One Farad when a charge of One Coulomb is stored on the plates by a voltage of One volt. Capacitance, C is always positive and has no negative units. However, the Farad is a very large unit of measurement to use on its own so sub-multiples of the Farad are generally used such as micro-farads, nano-farads and pico-farads, for example.

Standard Units of Capacitance



  • Micro farad  (μF)   1μF = 1/1,000,000 = 0.000001 = 10-6 F

  • Nano farad  (nF)   1nF = 1/1,000,000,000 = 0.000000001 = 10-9 F

  • Pico farad  (pf)   pf = 1/1,000,000,000,000 = 0.000000000001 = 10-12 F


CONSTRUCTION & WORKING  :


The basic construction of all capacitors is of two parallel metal plates separated by an insulating material.

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TYPES :


Capacitors are divided into two mechanical groups: Fixed capacitors with fixed capacitance values and variable capacitors with variable (trimmer) or adjustable (tunable) capacitance values.

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CAPACITOR IN SERIES & PARALLEL :


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