Figure below shows a balanced Wheat stone's network. If it is distributed by changing P to 22 ` Omega `, then which of the following steps will bring the bridge to balance again ?

Options

A. increasing S by `3Omega`
B. increasing Q by `20Omega`
C. increasing R by `50Omega`
D. both 'a' and 'b'

Answer

D

Explanation

To balance bridge, `(P)/(Q)=(S)/(R)`
For option (a), `(22)/(200)= (33)/(300)`
For option (b), `(22)/(220)=(30)/(300)`
For option(c), `(22)/(200)!=(30)/(350)`
Thus, bridge will balance by, (1) increasing S by `3 Omega` and (2) increasing Q by `20 Omega`.