question_answer

The equivalent resistance between X and Y in circuit given, is :

A)  5\[\Omega \]                                   

B)  7.5\[\Omega \]

C)  20\[\Omega \]                                

D)  10\[\Omega \]

Correct Answer: D

Solution :

                Given circuit is balanced Wheatstone bridge as \[\frac{P}{Q}=\frac{R}{S}\] hence between point MN, resistance \[10\Omega \] is in effective Therefore, equivalent circuits is                 Equivalent resistance between XY is                 \[=\frac{(10+10)(10+10)}{(10+10)+(10+10)}\]                                 \[=\frac{20\times 20}{40}=10\Omega \]