An electric lamp of resistance 20Ω and a conductor of resistance 4Ω are connected to a 6V battery as shown in the circuit. Calculate: (a) The total resistance of the circuit (b) The current through the circuit (c) The potential difference across the (i) Electric lamp and (ii) Conductor, and (d) Power of the lamp.

a). The total resistance of the circuit = 20Ω + 4Ω = 24Ω
b). The current through the circuit = current through the bulb = current through the conductor. The current through the circuit = voltage applied / Total Resistance. The current through the circuit = 6 / 24 amp. The current through the circuit = 0.25 amp
c). The potential difference across the lamp and the conductor (i) The potential difference across the electrical lamp = 0.25 × 20 = 5 volt (ii) The potential difference conductor = 0.25 × 4 = 1 volt
d). Power can be calculated as voltage across the lamp × current through the lamp. power = 5 × 0.25 → 1.25W.