NEET 2017 · PhysicsPotentiometerPrevious Year Question
A potentiometer is an accurate and versatile device to measure emf because the method involves:
Answer: (C) a condition of no current flow through the galvanometer. \textbf{Answer:} (3) no current through the galvanometer \textbf{Solution:} At null, no current is drawn from the test cell, so the true emf (not terminal PD) is measured.
- A.cells
- B.potential gradients
- C.a condition of no current flow through the galvanometer✓
- D.a combination of cells, galvanometer and resistances
Correct Answer
(C) a condition of no current flow through the galvanometer
Solution & Explanation
\textbf{Answer:} (3) no current through the galvanometer \textbf{Solution:} At null, no current is drawn from the test cell, so the true emf (not terminal PD) is measured.
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