Question 118 of 380

The equivalent resistance between $A\text{and}B$ is _______.
.

A$\dfrac{2}{3}\Omega$B$\dfrac{1}{2}\Omega$C$\dfrac{3}{2}\Omega$D$\dfrac{1}{3}\Omega$

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Answer: (A) $\dfrac{2}{3}\Omega$

Point D and G are at same potential. Same is the case with point E and F.
Now, resistance between DC and GC are in parallel combination. Similarly, resistance between CE and CF are in parallel combination. The modified circuit will be as shown below considering ${R}_{eq}=\dfrac{{R}_{1}{R}_{2}}{{R}_{1}+{R}_{2}}$ for parallel combination.

Therefore, we can write
$\dfrac{1}{{R}_{eq}}=\dfrac{1}{2}+\dfrac{1}{12}+\dfrac{1}{4}+\dfrac{1}{6}+\dfrac{1}{2}$
$=\dfrac{6+1+3+2+6}{12} =\dfrac{3}{2}$
$\Rightarrow {R}_{eq}=\dfrac{2}{3}\Omega$

JEE Main Physics practice question on Current Electricity (Combination of Resistances), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.