In the circuit `P != R, ` the reading of the galvanometer is same with switch S open or closed. Then

Options

A. `I_R = I_G`
B. `I_P = I_G`
C. `I_Q = I_G`
D. `I_Q = I_R`

Answer

A

Explanation

(a) Since the opening or
closing the switch does not affect the current through G,
it means that in both the
cases there is no current passing through S. Thus
potential at A is equal to
potential at B and it is the
case of balanced
wheatstone bridge. ...
`I_P = I_Q and I_R = I_G`