Six equal resistances are connected between points P, Q and R as shown in the figure. Then the net resistance will be maximum between

Options

A. `P` and `Q`
B. `Q` and `R`
C. `P` and `R`
D. any two points

Answer

A

Explanation

maximum resistance will be between `P` and `Q`
`R_(eq) = (R((R)/(3) + (R)/(2)))/(R+(R)/(3)+(R)/(2)) = (5 R^2//6)/(11 R//6) = (5 R)/(11)`
`R_(QR) = ((R)/(2)(R + (R)/(3)))/(11 R//6) = (2 R^2//3)/(11R//6) = (4 R)/(11)`
`R_(PR) = ((R)/(3)(R + (R)/(2)))/(11 R//6) = (R^2//2)/(11 R//6) = (3 R)/(11)`.