Question

Show how would you join three resistors each of resistance 9ohm so that the equivalent resistance of the combination is : (i)13.5ohm , (ii)6ohm ?

Answer 1

For getting total resistance 13.5 ohm, take 2 resistors as parallel and one series. 1/9 + 1/9=9/2+9=13.5
Then two series and one parallel.9+9=18.
So now take this series into parallel. 1/18+1/9=6.