Skip to main content

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.

Untitled-2.jpg

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.

Fixed_capacitors_overview.svg.png

CAPACITOR IN SERIES & PARALLEL :


Untitled-3.jpg
Labels:

Comments

Post a Comment

Popular posts from this blog

voltage

Voltage, is is the difference in potential between two points  in an electric field. also called electromotive force. voltage is the   pressure from an electrical circuit’s power source that pushes charged electrons (current).           grater the voltage grater the flow of electric current. Voltage is symbolized by   V or E . The standard unit is the volt. One volt will drive one columb  (6.24 x 10 18 ) charge.such as electronics through a resistance of one ohm. Voltage can be direct or alternating. A direct voltage maintains the same polarity. In an alternating voltage, the polarity reverses direction periodically. The number of complete cycles per second is the frequency which is measured in hertz.
3 comments
Read more

BJT (bipolar junction transistor)

A bipolar junction transistor is a three terminal semiconductor current controlled device with two P-N junctions. The three terminals are emitter(E), base(B) and collector(C). the emitter junction is heavily doped, base is less doped and made very thin and collector terminal is moderately doped. Collector has grater size than emitter and base terminal is thinner than both. (The thinner the base, the stronger the E-C electric field, and the larger the impact of a small current injected into the base. Explained clearly in active mode operation below) emitter terminal is moderate in size. A BJT has two types of transistors: NPN transistor PNP transistor NPN transistor : In an NPN transistor a p-type material is sandwiched between two n-type materials. [gallery ids="979,978" type="rectangular"] PNP transistor : In a PNP transistor a n-type material is sandwiched between two p-type materials. [gallery ids="989,990" type="rectangular"] Oper...
2 comments
Read more

tunnel diode

introduction : A tunnel diode is a highly doped semiconductor device that conducts current by quantum mechanical tunneling. it is also called as esaki diode named after leo esaki who got Nobel  prize in physics for discovering electron tunneling in 1973. Tunneling  Phenomenon: According to classical laws of physics, a particle must have an energy at least equal to the height of a potential-energy barrier if it has to move from one side of the barrier to the other. In other words, energy has to be supplied from some external source so that the electrons on one side of junction climb over the junction barrier to reach the other side. However if the barrier is thin such as in tunnel diode, the Schrodinger equation(Quantum Mechanics) indicates that there is a large probability that an electron will penetrate through the barrier. This will happen without any loss of energy on the part of electron. This quantum mechanical behavior is referred to as tunneling and the high-impurity P-N junctio...
1 comment
Read more