Capacitors, usually referred to as capacitance for their ability to hold charges, are denoted by the letter C. Definition 1: A capacitor, as the name implies, is a 'charged container', a device that holds charges. English name: capacitor. Capacitors are one of the electronic components widely used in electronic equipment, and are widely used in DC blocking, coupling, bypass, filtering, tuning loops, energy conversion, control, etc. in circuits. Definition 2: Capacitor, any two conductors (including wires) that are insulated from each other and are very close to each other form a capacitor.
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A capacitor is not the same as a capacitor. Capacitance is a basic physical quantity, the symbol C, and the unit is F (farad).
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General formula C=Q/U Special formula for parallel plate capacitors: electric field strength between plates E=U/d, capacitor capacitance determination formula C=εS/4πkd
With the rapid development of electronic information technology, the upgrading speed of digital electronic products is getting faster and faster. The production and sales of consumer electronic products such as flat-panel TVs (LCD and PDP), notebook computers, digital cameras and other products continue to grow, driving Capacitor industry growth.
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definition:
It is composed of a layer of insulating dielectric sandwiched between two metal electrodes. When a voltage is applied between two metal electrodes, charges are stored on the electrodes, so capacitors are energy storage elements. Any two conductors that are insulated from each other and in close proximity form a capacitor. A parallel plate capacitor consists of the plates of the capacitor and the dielectric.
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Features:
1. It has charge and discharge characteristics and the ability to prevent the passage of direct current and allow the passage of alternating current.
2. In the process of charging and discharging, the charge on the two plates has an accumulation process, that is, the voltage has a process of building up. Therefore, the voltage on the capacitor cannot be mutated.
Charging of the capacitor: the two plates are respectively charged with the same amount of different charges, and the absolute value of the charged amount of each plate is called the charged amount of the capacitor.
Discharge of the capacitor: The positive and negative charges at the two poles of the capacitor are neutralized by the wire. During the discharge process, a short current is generated on the wire.
3. The capacitive reactance of a capacitor is inversely proportional to frequency and capacity. That is to say, when analyzing the capacitive reactance, it is necessary to contact the frequency and capacity of the signal.
The capacitance formula of a parallel plate capacitor is:
The dielectric constant vacuum εr=1, k is the electrostatic force constant, S is the area facing the two plates, and d is the distance between the two plates.
Explanation: The electric field in a parallel plate capacitor is a uniform electric field