Current Electricity: Maximum Power – Proof MCQ

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Maximum Power – ProofHardQuestion 31684

Question

The maximum efficiency (fraction of total power delivered to load) when R_ext = r_internal is:

50%

P_ext/P_total = R/(R+r). At max power condition R=r: efficiency = r/(r+r) = 1/2 = 50%. Maximum power transfer is inherently only 50% efficient.