According to the Maximum Power Transfer Theorem, under what condition does an electrical source with internal resistance r deliver maximum power to a variable external load resistor R?

Answer and explanation

Correct answer: A. When the external load resistance equals the internal resistance (R = r)

.
  1. Step 1: Current in the circuit is .
  2. Step 2: Power delivered to the external load is .
  3. Step 3: To find the condition for maximum power, differentiate with respect to and set :
  4. Step 4: This yields .
  5. Step 5: The maximum power transferred is .
Answer
When the load resistance equals the internal resistance (R = r)
Why not the others: 'R = 0' gives because all power is dissipated internally; 'R -> ∞' gives and ; 'R = 2 r' gives sub-maximal power.

Practise more Current electricity.

Free questions with an explanation for every one, and full timed NEET UG mock tests.

All Current electricity questionsTake a mock test

More Current electricity questions