Question

In conversion of moving coil galvanometer into an ammeter of required range, the resistance of ammeter, so formed is ______.
[S = shunt and G = resistance of galvanometer]

विकल्प

• `("S + G")/"SG"`

• `"SG"/("S + G")`

• `("S - G")/"SG"`

• `"SG"/("S - G")`

Answer 1

In conversion of moving coil galvanometer into an ammeter of required range, the resistance of ammeter, so formed is `underline("SG"/("S + G"))`.

Explanation:

A moving coil galvanometer can be converted into an ammeter by connecting a low resistance (called shunt resistance) in parallel to it.

Hence, the resistance (R) of the ammeter, so formed is

`1/"R" = 1/"S" + 1/"G"`

R = `"SG"/("S + G")`