Answer: Remains unchanged.
- A Changes proportionally
- B Becomes twice as large
- C Remains unchanged
- D Becomes zero
Correct answer: C. Remains unchanged
Explanation: At balance, the potential difference between the galvanometer junctions is zero, so no current flows through the galvanometer. Its resistance therefore does not affect the balance condition.
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.