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

Determine the iron loss current, A transformer takes a current of 0.8A whe...

A transformer takes a current of 0.8A when its primary is connected to a 240 volt, 50Hz supply, the secondary being on open circuit. If the power absorbed is 72 watts, Determi

Resistors and resistors characteristics, A resistor is a two-terminal elect...

A resistor is a two-terminal electrical or electronic component that resists an electric current by producing a voltage drop between its terminals in the accordance with ohm’s law.

Experiment of serviceable spring balance, A serviceable spring balance ...

A serviceable spring balance The quality of rubber deteriorates rather rapidly in unfavourable climatic conditions; a coiled steel spring is preferable. The pattern defined ha

What is utilisation count, What is Utilisation Count? Utilisation Count...

What is Utilisation Count? Utilisation Count shows status of every processor in a particular mode it implies that overhead mode, idle mode and busy mode with respect to progres

Gravitation, l question.. a particle rest on the top of a h...

l question.. a particle rest on the top of a hemi spher radius R find the smallest horizondal velocity that must imparted to the particle if it''s to leave the hemi

Define electric field, Electric Field: The electrical field because of ...

Electric Field: The electrical field because of a charge can be described as the space around the charge.

Determine the vertical reaction, The boom DF and the column DE have a unifo...

The boom DF and the column DE have a uniform weight of P55 N/m and the chain and load at F is P56 kN.  Determine the Shear Force in kN rounded to 1 DP and the Bending Moment in kN.

The charge and discharge characteristics of lead battery, The charge and di...

The charge and discharge characteristics of lead battery: During discharge the plates are converted into lead sulphate, the water content of the electrolyte increases, the inte

Give three applications of photoelectric cells, Q. Give three applications ...

Q. Give three applications of photoelectric cells. (i) Photoelectric cells are utilized for reproducing sound in cinematography. (ii) They are utilized for controlling the

Voltage, Voltage: Voltage is the electrical equivalent of mechanical po...

Voltage: Voltage is the electrical equivalent of mechanical potential. If a person drops a rock from the first storey of a building, the velocity it will reach when dropped wi

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