Two unknown resistances are connected in two gaps of a meter bridge, null point is obtained at 40 cm from left end. A 30 resistance is connected in series with the smaller of the resistance, the null point shifts by 20 cm to the right end.
The value of smaller resistance in is
48
12
36
24
Let the two resistors have resistances x and y
Solving above equations we get x = 24 and y = 36
The value of smaller resistance in is 24.
Option 4 is correct