question_answer

The minimum resistance that can be obtained by connecting 5 resistances of \[\frac{1}{4}\Omega \]  each, is 4

A)  \[\frac{4}{5}\Omega \]

B)   \[\frac{5}{4}\Omega \]

C)  \[20\,\Omega \]                                             

D)  \[0.05\,\,\Omega \]

Correct Answer: D

Solution :

                 When resistances are connected in series, resultant resistance is equal to sum of individual resistances and in parallel resultant resistance is equal to sum of reciprocal of individual   resistance,   hence   minimum resistance is obtained when the five resistances are connected in parallel.                                 Hence, equivalent resistance is\[{{R}_{p}}=\frac{1/4}{5}=\frac{1}{20}=0.05\,\,\Omega \]