Draw a schematic circuit diagram consisting a battery, a plug key, an ammeter and a bulb all connected in series with a voltmeter connected in parallel with the bulb.

Charge, Q = 5 C
Potential across the battery, V = 12 V

Energy given by battery = Charge x Potential difference  
                                     = 5 C  x  12 V
                                     = 60 J. 

Given, 

Charge, Q = 2 C
Potential difference across the two ends, V = 12 V 

Work done in moving a charge, W = QV
                                                    = 2 C x 12 V
                                                    = 24 J. 

Ohm’s law: Ohm's law states that the current (I) flowing through a conductor is directly proportional to the potential difference (V) applied across its ends, provided the temperature and other physical conditions remain unchanged. 

Mathematically, V ∝ I 

                        V = RI 

The proportionality constant R is called the resistance of the conductor.