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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

## Alternating current

It is that current whose direction changes with time. in order tousreverses continuously. The end A, of the resistor is earthed i.e. at zero and the voltage of end B, varies with time in a way represented in the fiegure(b) the electric current in the resisor R, then flows as shown in the figure, the shape of the graph remains the sameduring the time interval 0, to T & T to 2T etc. The interval of time after which the value of electric current repeats itselfis calledtime period T and the electric current is said to have completed one cycle. During the time interval 0 to T/2, the current increases from 0 to certain maximum value and then again falls to zero. Simmilarly during time interval T/2 to T, the electric current varries in the same manner but in opposite direction. Such a flow of current is called Alternating Current.

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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