Current Electricity · Class 12 · CBSE · Science Physics
A cell of emf E and internal resistance r is connected across an external resistance R. The maximum power is delivered to the external resistance whe…
Practice question from Current Electricity (Class 12 · CBSE · Science Physics), with the correct answer and a step-by-step solution.
medium · MCQ · Q-DA1BD8
A cell of emf and internal resistance is connected across an external resistance . The maximum power is delivered to the external resistance when:
- A.R = rCorrect answer
- B.R = 2r
- C.R = r/2
- D.R >> r
Solution
Power delivered to the external load is given by . For maximum power, , which yields .
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