In a potentiometer experiment, it is found that no current passes through the galvanometer when the terminals of the cell are connected across 0.52 m of the potentiometer wire. If the cell is shunted by a resistance of 5 Ω, balance is obtained when the cell is connected across 0.4 m of the wire. Find the internal resistance of the cell.

Question

In a potentiometer experiment, it is found that no current passes through the galvanometer when the terminals of the cell are connected across 0.52 m of the potentiometer wire. If the cell is shunted by a resistance of 5 Ω, balance is obtained when the cell is connected across 0.4 m of the wire. Find the internal resistance of the cell. (A) 0.5 Ω (B) 1 Ω (C) 1.5 Ω (D) 2 Ω

Tardigrade Admin · Accepted Answer

r=R[(l1/l2)-1] =5[(0.52/0.4)-1] =5[1.3-1]=1.5 Ω

$0.5 Ω$

$1 Ω$

$1.5 Ω$

$2 Ω$

$r = R [\frac{l _{1}}{l _{2}} - 1]$
$= 5 [\frac{0.52}{0.4} - 1]$
$= 5 [1.3 - 1] = 1.5 Ω$

0.5Ω

1Ω

1.5Ω

2Ω

r=R[l2​l1​​−1] =5[0.40.52​−1] =5[1.3−1]=1.5Ω

$0.5 Ω$

$1 Ω$

$1.5 Ω$

$2 Ω$

$r = R [\frac{l _{1}}{l _{2}} - 1]$
$= 5 [\frac{0.52}{0.4} - 1]$
$= 5 [1.3 - 1] = 1.5 Ω$