Question

A Daniel cell is balanced on 125 cm lengths of a potentiometer wire. Now the cell is short circuited by a resistance 2 Ω and the balance is obtained at 100 cm. The internal resistance of the Daniel cell is ______.

विकल्प

• 0.5 Ω

• 1.5 Ω

• 1.25 Ω

• 4/5 Ω

Answer 1

A Daniel cell is balanced on 125 cm lengths of a potentiometer wire. Now the cell is short circuited by a resistance 2 Ω and the balance is obtained at 100 cm. The internal resistance of the Daniel cell is 0.5 Ω.

Explanation:

r = `("l"_1/"l"_2-1)`R

= `(125/100-1)2`

= 0.25 × 2

= 0.5 Ω