Answer: 16 W.
- A 8 W
- B 16 W
- C 24 W
- D 32 W
Correct answer: B. 16 W
Explanation: Each piece has resistance 16/4 = 4 Ω. Each parallel pair has equivalent resistance 2 Ω. The two branches in series give 4 Ω. Therefore P = V<sup>2</sup>/R = 8<sup>2</sup>/4 = 16 W.
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.