question_answer

What is the effective resistance between points P and Q in the circuit shown below?

A) \[0.\text{15  }\Omega \]

B) \[0.\text{66 }\Omega \]              

C) \[\text{1}.\text{5 }\Omega \]                                   

D) \[\text{1}.\text{75 }\Omega \]

Correct Answer: C

Solution :

\[\frac{1}{R}=\frac{1}{{{R}_{1}}}+\frac{1}{{{R}_{2}}}+\frac{1}{{{R}_{3}}}\] Where \[\frac{1}{R}=\frac{1}{6}+\frac{1}{3}+\frac{1}{6}=\frac{1+2+1}{6}=\frac{4}{6}\] Or \[R=\frac{6}{4}=1.5\,\Omega \]