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

What fraction of the sample will be left over, Q. Tritium has a half life p...

Q. Tritium has a half life period of 12.5 years. What fraction of the sample will be left over after 25 years? HLP = 12.5 years Number of HLPs in 25 years = 25 / 12.5 =2

Explain moseleys law, What do you mean by Moseley's law? Explain briefly it...

What do you mean by Moseley's law? Explain briefly its importance. Explain the origin of X-ray spectra. Describe continuous and characteristic x-ray spectrum.

Properties of superconductors, (1)            The  current in a super c...

(1)            The  current in a super conductor once set up continuous for a very long time without attenuations. (2)          The permeability  of a super conducto

Determine the mass number of the element, Determine the mass number of the ...

Determine the mass number of the element? A mass of 25.2 g of an element is known to contain 6.77x 10 23 atoms. What is the mass number of the element? I thought it would be

Spectral lines , The spectral lines arising from the transition of electron...

The spectral lines arising from the transition of electron forms a spectra series.  Mainly there are five series and every series is named after it's discover as Lymen series, B

What is the moment of inertia, A student sits on a stool holding a 5.0-kg d...

A student sits on a stool holding a 5.0-kg dumbbell in both hands. He extends his arms such that each dumbbell is 0.60 m from the axis of rotation. The student's moment of

What is the velocity, An ice-skater with a mass of 75.0 kg pushes off again...

An ice-skater with a mass of 75.0 kg pushes off against a second skater with a mass of 42.0 kg. Both skaters are initially at rest. After the push, the larger skater moves

Angular velocity is contiguously decreasing, Which graph represents the ang...

Which graph represents the angular velocity as function of time in which the magnitude of angular velocity is contiguously decreasing? Ans) That is down parabola from origin gra

Explain about the term simulated absorption in brief, Explain about the ter...

Explain about the term simulated absorption in brief. Stimulated absorption: a. For the photon-atom interaction to happen, the energy of the interacting photon h? must match

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