question_answer

In the circuit shown, the resistance r is a variable resistance. If for r = fR, the heat generation in r is maximum then the value of f is :   JEE Main Online Paper (Held On 09 April 2016)

A) 1                                             

B) \[\frac{3}{4}\]

C) \[\frac{1}{4}\]                                   

D) \[\frac{1}{2}\]

Correct Answer: D

Solution :

to get maximum heat generation from r. \[r={{\operatorname{R}}_{eq}}=R/2\]