In a potentiometer experiment the galvanometer shows no deflection when a cell is connected across 60 cm of the potentiometer wire. If the cell is shunted by a resistance of 6 Ω the balance is obtained across 50 cm of the wire. The internal resistance of the cell is

Question

In a potentiometer experiment the galvanometer shows no deflection when a cell is connected across 60 cm of the potentiometer wire. If the cell is shunted by a resistance of 6 Ω the balance is obtained across 50 cm of the wire. The internal resistance of the cell is (A) 0.5 Ω  (B) 0.6 Ω  (C) 1.2 Ω  (D) 1.5 Ω

Tardigrade Admin · Accepted Answer

For potentiometer, the internal resistance r, is given by r=((l1/l2)-1) R Given, l1=600 cm, l1=50 cm R=6 Ω ∴ r=((60/50)-1) 6=1.2 Ω

Q. In a potentiometer experiment the galvanometer shows no deflection when a cell is connected across $60 c m$ of the potentiometer wire. If the cell is shunted by a resistance of $6 Ω$ the balance is obtained across $50 c m$ of the wire. The internal resistance of the cell is

$0.5 Ω$

$0.6 Ω$

$1.2 Ω$

$1.5 Ω$

For potentiometer, the internal resistance $r$ , is given by
$r = (\frac{l _{1}}{l _{2}} - 1) R$
Given, $l_{1} = 600 c m$ ,
$l_{1} = 50 c m$
$R = 6 Ω$
$∴ r = (\frac{60}{50} - 1) 6 = 1.2 Ω$

Q. In a potentiometer experiment the galvanometer shows no deflection when a cell is connected across 60cm of the potentiometer wire. If the cell is shunted by a resistance of 6Ω the balance is obtained across 50cm of the wire. The internal resistance of the cell is

0.5Ω

0.6Ω

1.2Ω

1.5Ω