When the resistance of 9 ohm is connected at the ends of a battery its terminal voltage decreases from 40 volt to 30 volt. The internal resistance of the battery is

Question

When the resistance of 9 ohm is connected at the ends of a battery its terminal voltage decreases from 40 volt to 30 volt. The internal resistance of the battery is (A) 6 ohm (B) 3 ohm (C) 9 ohm (D) 15 ohm

Tardigrade Admin · Accepted Answer

Initially when no current flows, the terminal voltage will be emf so ε = 40V. The internal resistance o f battery is given by r=((E/V)-1) R =((40/30)-1) 9 =(9 × 10/30)=3 ohm

Q. When the resistance of 9 ohm is connected at the ends of a battery its terminal voltage decreases from $40$ volt to $30$ volt. The internal resistance of the battery is

6 ohm

3 ohm

9 ohm

15 ohm

Initially when no current flows, the terminal voltage will be emf so $ε = 40 V$ . The internal resistance o f battery is given by
$r = (\frac{E}{V} - 1) R$
$= (\frac{40}{30} - 1) 9$
$= \frac{9 \times 10}{30} = 3$ ohm

Q. When the resistance of 9 ohm is connected at the ends of a battery its terminal voltage decreases from 40 volt to 30 volt. The internal resistance of the battery is