A galvanometer of resistance `G` is shunted by a resistance `S ohm`. To keep the main current in the circuit uncharged, the resistnace to be put in series with the galvonmeter

Options

A. `G^(2)/( S + G)`
B. `G/(S +G)`
C. `S^(2)/(S +G)`
D. `(SG)/(S + G)`

Answer

A

Explanation

`G = ((GS)/(G + S)) + S^(.)`
`rArr S = G -(GS)/99 rArr S. = G^(2)/(G + S.)`