Answer: 1.0 A.
- A 0.5 A
- B 2.0 A
- C 1.0 A
- D 3.0 A
Correct answer: C. 1.0 A
Explanation: Let the clockwise loop currents be I<sub>1</sub> and I<sub>2</sub>. Kirchhoff equations are 10 = 2I<sub>1</sub> + 2(I<sub>1</sub> - I<sub>2</sub>) and 4 = 2I<sub>2</sub> + 2(I<sub>2</sub> - I<sub>1</sub>). Solving gives I<sub>1</sub> = 4 A and I<sub>2</sub> = 3 A. The common resistor carries |I<sub>1</sub> - I<sub>2</sub>| = 1 A.
In series, the same current flows through both resistors; in parallel, the current splits between branches and the voltage across each resistor is the same.
Concept context
Ohm's law, resistors, Kirchhoff's laws, Wheatstone bridge, and cells.