Electrostatics, Physics

An uncharged capacitor with a solid dielectric is connected to a similar air capacitor charged to a potential of V0. If the common potential after sharing of charges becomes V, then the dielectric constant of the dielectric must be ?

Solution)
Capacitor or condenser, device for the storage of electric charge. Simple capacitors have two plates made of an electrically conducting material (e.g., a metal) and divided by a nonconducting material or dielectric (e.g., glass, paraffin, mica, paper, oil, tantalum, or air). The Leyden jar is a simple capacitor. If an electrical potential (voltage) is applied to the plates of a capacitor (e.g., by connecting one plate to the positive and the other to the negative terminal of a storage battery), the plates will become charged, one positively and one negatively. If the externally applied voltage is then removed, the plates of the capacitor remain charged, and the presence of the electric charge induces an electrical potential between the plates. This phenomenon is known as electrostatic induction. The capacity of the device for storing electric charge (i.e., its capacitance) can be increased by increasing the area of the plates, by decreasing their separation, or by changing the dielectric. The dielectric constant of a particular dielectric is the measure of the dielectric''s unit capacitance. It defines the ratio of the capacitance of a dielectric-filled capacitor to a capacitor of the similar size with a vacuum between the plates. Capacitors are used in many electrical and electronic devices. The main capacitor classifications are non-polarized (used for AC circuits) and polarized (used for DC circuits). Capacitors can also be classified as fixed or variable. One type of variable capacitor, formerly used in radio and television tuning circuits, consisted of two sets of semicircular plates, one fixed and the other mounted on a movable shaft. By rotating the shaft the area of overlap of the two plates increases or decreases, therefore increasing or decreasing the capacitance. These devices have largely been replaced by frequency synthesizers and a special type of solid-state diode, known as a varactor, whose capacitance changes with the reverse-biased voltage across it.

Posted Date: 3/9/2013 7:21:58 AM | Location : United States







Related Discussions:- Electrostatics, Assignment Help, Ask Question on Electrostatics, Get Answer, Expert's Help, Electrostatics Discussions

Write discussion on Electrostatics
Your posts are moderated
Related Questions
Define the term multi-mode fibre shortly. Multi-mode fibre: This type of fibre permits more than one mode to travel by this. As this has to permit more number of modes to tr

1. Particle travels in straight line and the motion is periodic 2. The acceleration of particle is always proportional to the displacement from the equilibrium position and alwa

Cermets are a hybrid mixture of ceramic and metal. These are made by screening a mixture of glass and metal oxide on to a ceramic substrate. It is then fired at a temperature high


Two long wires a and b, carrying equivalent currents of 10 A, are placed parallel to each other with a separation of 4 cm among them as shown in figure. Find the magnetic field B a

quenching process in g.m. counter

Energy Transformation for Downhill Skiing Downhill skiing is a typical describe of the relationship among work and energy. The skier starts at an elevated position, therefore p

Conservation of angular momentum The overall angular momentum of any closed system remains constant. There are many other laws which deal with particle physics, as conserv

Q. What are electromagnetic waves? As-per to Maxwell a speed up charge is a source of electromagnetic radiation. In an electromagnetic wave electric as well as magnetic field

Explain about the dispersion in optical fibres. Dispersion in optical fibres: Into optical fibers, temporal distribution of optical pulses because of dispersion will lead to