question_answer

A uniform wire of \[16\,\Omega \] resistance is made into the form of a square. Two opposite corners of the square are connected by a wire of resistance \[16\,\Omega .\] The effective resistance between the other two opposite comers is

A)  \[32\,\Omega \]                             

B)  \[16\,\Omega \]

C)  \[8\,\Omega \]               

D)         \[4\,\Omega \]

Correct Answer: D

Solution :

The circuit will be as shown in figure. It is a balanced Wheatstone bridge, so the effect of \[16\,\Omega \] resistance will be absent. Then effective resistance between A and B is                 \[=\frac{8\times 8}{8+8}=4\,\Omega \]