can u solve(emf)

emf= Electro Motive Force-- and is generated at the source,it builds up the P.D. if that answers your question.?

you need to elaborate more .

hi, sak

u said emf is generated at the source, ok think we have motor connected across source and voltmeter. so we supplied the supply to motor our voltmeter will show some voltage, now if we remove the supply what will read by voltmeter will it come to zero immediately or gradually. if gradually then it means emf is supply by motor?....

Yes-Due to megnetic remenance ,take any electrical motor and connect a volt meter across the terminal and rotate the motor ,there will be some voltage readings on the meter,a similar effect is used in power generators(on start up) but the voltage is then build -up and controlled by AVR and excitor coils.

There is also the back emf which will bring down the voltage gradually to a certain level

Remember the motor coils are inductors and store some power.

So what if it comes down slowly? That happens due to the stored energy by inductor. Just like in the case of a capacitor connected to a battery.

Capacitor is charged by battery not that battery is charged by capacitor.

Now think this way.

Remove your motor and battery from one other and take a voltmeter, measure the voltage on both terminals of both the items.

And record the result where do you get the emf? On motor or on battery?