An ammeter has resistance R0 and range i . What resistance should be connected in parallel with it to increase its range by ni ?

Question

An ammeter has resistance R0 and range i . What resistance should be connected in parallel with it to increase its range by ni ? (A) R0/(n - 1) (B) R0/(n + 1) (C) R 0 / n ⁡ (D) None of these

Tardigrade Admin · Accepted Answer

Given, i g â¡ = i â¡ , G â¡ = R â¡0 ; i1=n i+iâ¡=(n â¡ + 1)iâ¡ ∴ S =(i â¡g â¡ G â¡/i1 â¡ - i â¡g â¡)=(i â¡ R â¡0/(n â¡ + 1) i â¡ - i â¡)=(R â¡0/n â¡)

Q. An ammeter has resistance $R_{0}$ and range $i$ . What resistance should be connected in parallel with it to increase its range by $ni$ ?

$R_{0} / (n - 1)$

$R_{0} / (n + 1)$

$R_{0} / n$

None of these

Given, $i_{g} = i, G = R_{0}$ ;
$i_{1} = ni + i = (n + 1) i$
$∴ S = \frac{i _{g} G}{i _{1} - i _{g}} = \frac{i R _{0}}{( n + 1 ) i - i} = \frac{R _{0}}{n}$

Q. An ammeter has resistance R0​ and range i . What resistance should be connected in parallel with it to increase its range by ni ?

R0​/(n−1)

R0​/(n+1)

R0​/n⁡