JEE Main 2016 — Current Electricity Question with Solution
From: JEE Main 2016 (Online) 9th April Morning Slot
Question
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 :
This question includes a diagram. The text above accompanies the figure.
Choose an option
Show full solutionCorrect option: B
Correct answer
B
Step-by-step explanation
Here equivalent resistance
Req = R +
= R +
= R +
=
Circuit current,
=
=
Current in the resistance r,
I = =
Heat generated in r,
H =
=
For maximum H,
= 0
= 0
2f + 1 = 4f
2f = 1
f =
Req = R +
= R +
= R +
=
Circuit current,
=
=
Current in the resistance r,
I = =
Heat generated in r,
H =
=
For maximum H,
= 0
= 0
2f + 1 = 4f
2f = 1
f =
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This is a previous-year question from JEE Main 2016, covering the Current Electricity chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.