Question 24
Current ElectricityA resistance R is connected across the terminal of an electric cell of internal resistance 2 Ω and the voltage was reduced to 3/5 of its nominal value. The value of R is
- A.3 Ω
- B.2 Ω
- C.1 Ω
- D.6 Ω
Show the answer and explanation
Answer: A (3 Ω)
Explanation
Terminal p.d. = E × R/(R + r) = 3/5 E, so 5R = 3R + 6 and R = 3 Ω.