Answer: Unknown resistance.
- A Current in typical laboratory settings
- B Voltage under usual circumstances
- C Unknown resistance
- D Power according to most researchers
Correct answer: C. Unknown resistance
Explanation: Wheatstone bridge accurately measures unknown resistance by balancing the bridge so that galvanometer shows zero.
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.