(a) Name a device which helps to maintain potential difference across a conductor (say, a bulb).
(b) If a potential difference of 10 V causes a current of 2 A to flow for 1 minute, how much energy is transferred?
(a) A battery or cell helps to maintain potential difference across a conductor.
(b) 1 minute = 60 seconds
E = VIt = 10×2×60=1200 J