Electromotive force – emf, Physics

Assignment Help:

ELECTROMOTIVE FORCE – EMF:

To make use of electricity by provision of an electric current, the potential different must be maintained. That is, the positive and negative charge must be continuously replenished. A cell (or battery) uses chemical energy to maintain the potential difference.

Another device used for this purpose is the generator, which uses electro-mechanical energy to maintain the potential difference. The potential difference across the terminals of the source (cell, battery or generator) when it is not supplying current, is called Electromotive Force (emf), since this is a measure of the force available to push electrons around the circuit. In a circuit with a current flowing, the potential difference across the terminals of the source is always less than the emf and is referred to as the terminal voltage.


Related Discussions:- Electromotive force – emf

Micrometer simulation, Micrometer Simulation A Micrometer is used to me...

Micrometer Simulation A Micrometer is used to measure the external dimensions of objects that are 3 cm or smaller, this provides precise measurements to inside 0.01 mm. The

How far down is the surface of the water, A hiker tosses a rock into a cany...

A hiker tosses a rock into a canyon. He hears it strike water 4.78 s later. How far down is the surface of the water?

What do you mean by a junction diode, What do you mean by a junction diode....

What do you mean by a junction diode. Illustrate the formation of depletion layer at the junction. Describe the variation of depletion layer in forward and reverse biased condition

Describe how dewar flasks limit energy transfer, Describe how Dewar flasks ...

Describe how Dewar flasks limit energy transfer A Dewar flask (thermos)  is a device that resists energy transfer. Explain how Dewar flasks limit energy transfer by listing the

Compute the pitching motion of the spacecraft, A spacecraft design similar ...

A spacecraft design similar to GEOSAT proposes to use passive gravity-gradient stabilization for pitch attitude control (motion about the y-axis).  The satellite consists of a tip

Light absorbing materials in solar cells, All solar cells require a light a...

All solar cells require a light absorbing material contained within the cell structure to absorb photons and generate electrons via the photo voltaic effect. The materials used in

When a semiconductor is doped with a p-type impurity, When a semiconductor ...

When a semiconductor is doped with a P-type impurity, each impurity atom will (A) Acquire negative charge.                        (B) Acquire positive charge. (C) Remain

Fluid density and viscosity, The drag on a 30-ft long, vertical, 1.25-ft di...

The drag on a 30-ft long, vertical, 1.25-ft diameter pole subjected to a 30 mph air wind is to be determined with a model study. It is expected that the drag is a function of the p

Modulation and transmission, The amplified video signals are amplitude modu...

The amplified video signals are amplitude modulated using a suitable r.f. carrier wave in a transmitter called ‘AM' picture transmitter. Similarly, the amplified audio signals are

Calculate power required to operate the fan, A centrifugal fan is used to p...

A centrifugal fan is used to pump air. The fan rotor is 1 ft in diameter, and the blade spacing is 2 in. The air enters with no angular momentum and exits radially with respect to

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd