Practice mode Current Electricity

For a source of fixed emf and internal resistance r, the power delivered to an external load R is maximum when ____.

Correct answer B. R = r

Explanation

By the maximum power transfer theorem, power P = E²R/(R + r)² is largest when the load resistance equals the internal resistance of the source, R = r.

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For a source of fixed emf and internal resistance r, the power delivered to an external load R is maximum when ____.

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For a source of fixed emf and internal resistance r, the power delivered to an external load R is maximum when ____.

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