Q.
If in the circuit, power dissipation is $150\ W,$ then $R$ is
A) $2\ \Omega$
B) $6\ \Omega$
C) $5\ \Omega$
D) $4\ \Omega$
Explanation
(b) $P = \frac{V^{2}}{R_{eq}} \Rightarrow 150 = \frac{(15)^{2}}{\lbrack 2R/(R + 2)\rbrack} = \frac{225 \times (R + 2)}{2R}$
$\Rightarrow R = \frac{450}{75} = 6\Omega$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.