JEE Main · PhysicsHard
A battery of emf $E$ and internal resistance $r$ is connected to a variable resistor $R$. The power delivered to the resistor is maximum when $R$ equals $r$. What is the efficiency of the battery at this condition?
- A.$25\%$
- B.$50\%$
- C.$75\%$
- D.$100\%$
Show correct answer & step-by-step solution
Correct answer: B — $50\%$
Solution
Efficiency . For , or .
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