question_answer

If in the circuit, power dissipation is 150 W, then R is                                          [AIEEE 2002]

A) \[2\,\,\Omega \]

B) \[6\,\,\Omega \]

C) \[5\,\,\Omega \]

D) \[4\,\,\Omega \]

Correct Answer: B

Solution :

[b] As power \[P=\frac{{{V}^{2}}}{{{R}_{net}}}\] (as V is constant in parallel)

\[\Rightarrow \]            \[150=\frac{{{(15)}^{2}}}{\frac{R\times 2}{2+R}}\Rightarrow R=6\,\,\Omega \]