Question 41
Current ElectricityA galvanometer of internal resistance 50 Ω has a full scale deflection for a current of 5 mA. What is the resistance required to convert it to a voltmeter with full scale deflection of 10 V?
- A.1750 Ω
- B.1950 Ω
- C.2000 Ω
- D.2500 Ω
Show the answer and explanation
Answer: B (1950 Ω)
Explanation
Total resistance = 10 ÷ 0.005 = 2000 Ω. Subtract the galvanometer's 50 Ω: a 1950 Ω resistor is needed in series.