Question

A cell of internal resistance $X$ ohms drives current through an external resistance of 6 ohms. The power delivered by the cell to the external resistance will be maximum when

• A. $X=6\Omega$
• B. $X=3\Omega$
• C. $X=4\Omega$
• D. $X=0\Omega$

Answer 1

The correct option is D $X=0\Omega$


$P_{\text{max}}$ when $i$ is maximum.

$i=\frac{\in }{6+X}$

$i$ is maximum when $X=0$