3.1 The storage battery of a car has an emf of 12 V. If the internal resistance of the battery is 0.4 , what is the maximum current that can be drawn from the battery?

Emf of the battery, E = 12 V

Internal resistance of the battery, r = 0.4 Ω

Maximum current drawn from the battery = 1

According to Ohm's law,

E=Ir
I=Er
=120.4=30 A

The maximum current drawn from the given battery is 30 A.