Question Detail
Question
Two identical batteries, each 18V and 1Ω internal, wired in parallel across a 4Ω resistor. Current in the 4Ω resistor is?
Correct Answer
Option C is the correct answer.
Detailed Explanation
E_eq = 18V. r_eq = 1/2 = 0.5Ω. I = E_eq/(R + r_eq) = 18/(4+0.5) = 4A.
Hint
Combine internal resistances in parallel, then use Ohm's law.