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

Explain the molecular theory of surface tension, (i)  On the average, parti...

(i)  On the average, particles are separated by a distance of the order of 10-10 m and exert a force of attraction of the order of 10-11 N on each other. (ii)  The force of atta

Explain the term resistivity, Explain the term 'resistivity' and write its ...

Explain the term 'resistivity' and write its S. I . unit. Derive the expression for the resistivity of a conductor in terms of number density of free electrons and relaxation time.

Show the conditions for total internal reflection, Show the conditions for ...

Show the conditions for total internal reflection to happen. Arrive at the relation between refractive index and critical angle. What do you mean by optical fibre? on what rules do

Polymers, explanation on polymers tga curves

explanation on polymers tga curves

Determine tension in pulley problems, Three equal weights A, B, C of mass 2...

Three equal weights A, B, C of mass 2 kg each are hanging on a string passing over a fixed frictionless pulley as shown. Tension in the string connecting weights B and C is approxi

Determine the component of the force, Water flows through a right angle val...

Water flows through a right angle valve at the rate of 1000 lbm/s as shown in the figure. The pressure just upstream of the valve is 90 psi and the pressure drop across the valve i

Motion in one dimension, A packed parachute is dropped from rest from an ai...

A packed parachute is dropped from rest from an airplane. A daredevil is launched straight down rom the plane 3.00s later. Neglecting air resistance, the daredevil catches up to th

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