The resistance of the series combination of two resistances is S. When they are joined in parallel the total resistance is P. If S= nP then the minimum possible value of n is

Answer

4

Explanation

In series combination `S = (R_(1) +R_(2))`
In parallel combination ` , P = (R_(1)R_(2))/((R_(1)+R_(2)))`
`because (R_(1) +R_(2)) = n (R_(1)R_(2))/((R_(1)+R_(2)))`
`:. (R_(1)+R_(2))^(2) = nR_(2) R_(2)`
For minimum value `R_(1) = R_(2) =R `
`(R+R)^(2) = n (R xx R)`
`implies 4R^(2) = nR^(2) `
`implies n =4`