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 Electric charge One Coulomb Charge Production of electric charge Detection of electric charge Experiment to detect the electric charge Electrical conductors and insulators Electric field Electrostatic forces Application of electrostatic forces Electric current One Ampere of electric current Direction of electric current Basic relation of electric current Direct current Alternating current Ammeter Electromotive force - (e.m.f.) Potential difference One Volt Explanation of potential difference Measurement of potential difference Voltmeter Resistance Affect of length of the conductor on resistance Affect of cross-sectional area on resistance Affect of temeprature on resistance How nature of material affects the eresistance Ohm's law Potential difference - Current graph for Ohmic conductors Potential difference - Current graph for tungsten filament Potential difference - Current graph for semiconductor diode Electrical energy Formula for electrical energy Electrical Power Formulae for electrical power

## Formula for electrical energy

In the above figure, when the current passe through R, heat is produced across the resistor. By definition

V = W / Q

W = VQ

i.e. W, work is obtained when a charge 'Q' flows between two points maintained at a potential diference of V. Across a conductor this work may appear as heat energy as a result the temperature of the conductor rises.

electric current is the rate of flow of charge if current 1 amp, flows for 't' seconds between two poits then the charge (Q = It) flows between those ponits in time 't', then amount of energy obtained by the current during time 't' is

W = QV = VIt

If a current of I(ampere) is flowing through a resistor R, ohms, whose ends are maintained at potential difference V(volts) then by Ohm's law

V = IR

Hence W = VIt

or W = I2Rt

The electrical energy W in the resistor is dissipated as heat energy.

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 student Said : what the hell....there are no diagrams how are we supposed to understand? for lord's sake Do you even give a shit about stuff like this? 09/01/18 06:44 PM

 sree Said : wish these had a diagrams 24/12/15 10:01 AM

 student 567 Said : There are no diagrams, but seeing that you don't give a shit... why should i bother to comment?! Can you just put the dam diagram up already! 18/04/14 08:10 PM

 Deepak varun Said : there is a spelling mistake to say said they said asaid please change it admin 17/11/13 06:26 AM

 gargi sachdev Said : diagrams aren't there ... 29/08/12 12:35 AM

 gargi sachdev Said : diagrams aren't there ... 29/08/12 12:35 AM

 Ajay Said : I cant see any diagrams? can u help me with it------------------------------------------------------------------------------------- Admin Replied: Hi Ajay, thank you for informing us about this issue. We will make sure we make those images available for you as soon as possible. Thank you 15/03/12 12:13 PM