Question 27
Current ElectricityA cell of internal resistance 0.01 Ω can be measured accurately using the
- A.Ohm-meter
- B.potentiometer
- C.electroscope
- D.metre bridge
Show the answer and explanation
Answer: B (potentiometer)
Explanation
A potentiometer draws no current at balance, so it can compare e.m.f. and terminal p.d. accurately enough to find a very small internal resistance.