In the potentiometer circuit shown in the figure, the balance length AJ = 58 when switch S is open. When switch S is closed and the value of R=5 Ω , balance length AJ' = 50 cm. The internal resistance of the cell C' is

Question

In the potentiometer circuit shown in the figure, the balance length AJ = 58 when switch S is open. When switch S is closed and the value of R=5 Ω , balance length AJ' = 50 cm. The internal resistance of the cell C' is (A)  1.2 Ω  (B)  1.0 Ω  (C)  0.8 Ω  (D)  0.6 Ω

Tardigrade Admin · Accepted Answer

Here, l1=60 cm, l2=50 cm, R=5 Ω ε=kl1 where k is the potential gradient across the wire V=Kl2 ∴ (ε/V)=(l1/l2) =(60/50)=(6/5) Internal resistance of the cell is r=((ε/V)-1) R=((6/5)-1) 5=1.0 Ω

Q. In the potentiometer circuit shown in the figure, the balance length $A J = 58$ when switch $S$ is open. When switch S is closed and the value of $R = 5 Ω$ , balance length $A J^{'} = 50 c m$ . The internal resistance of the cell $C^{'}$ is

$1.2 Ω$

$1.0 Ω$

$0.8 Ω$

$0.6 Ω$

Q. In the potentiometer circuit shown in the figure, the balance length AJ=58 when switch S is open. When switch S is closed and the value of R=5Ω , balance length AJ′=50cm. The internal resistance of the cell C′ is

1.2Ω

1.0Ω

0.8Ω

0.6Ω

Here, l1​=60cm, l2​=50cm, R=5Ω ε=kl1​ where k is the potential gradient across the wire V=Kl2​ ∴Vε​=l2​l1​​ =5060​=56​ Internal resistance of the cell is r=(Vε​−1) R=(56​−1) 5=1.0Ω

Q. In the potentiometer circuit shown in the figure, the balance length $A J = 58$ when switch $S$ is open. When switch S is closed and the value of $R = 5 Ω$ , balance length $A J^{'} = 50 c m$ . The internal resistance of the cell $C^{'}$ is

$1.2 Ω$

$1.0 Ω$

$0.8 Ω$

$0.6 Ω$