a. A lamp of resistance 15 is connected to a battery of e.m.f. 4.5 V. Calculate

Question:

a. A lamp of resistance 15 Ω is connected to a battery of e.m.f. 4.5 V.
Calculate the current in the lamp.
b. Calculate the resistance of the filament of an electric heater that takes a current of 6.5 A when it is connected across a mains supply of 230 V.
C. Calculate the voltage that is required to drive a current of 2.4 A through a wire of resistance 3.5 Ω.