Answer: 6 ohm.
- A 4 ohm
- B 6 ohm
- C 9 ohm
- D 12 ohm
Correct answer: B. 6 ohm
Explanation: Series: 6+6=12 ohm. Parallel with 12 ohm: 1/R = 1/12 + 1/12 = 2/12. R = 6 ohm.
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.