Name a device that helps to maintain a potential difference across a conductor.

Draw a schematic diagram of a circuit consisting of a battery of three cells of $2\, V$ each,a $5\,\Omega$ resistor,an $8\,\Omega$ resistor,and a $12\,\Omega$ resistor,and a plug key,all connected in series. Include an ammeter to measure the current through the resistors and a voltmeter to measure the potential difference across the $12\,\Omega$ resistor. What would be the readings in the ammeter and the voltmeter?

On what factors does the resistance of a conductor depend?

An electric bulb is rated $220\, V$ and $100\, W$. When it is operated on $110\, V$,the power consumed will be ....... $W$.

Why are coils of electric toasters and electric irons made of an alloy rather than a pure metal?

What determines the rate at which energy is delivered by a current?