# When the terminals of a cell are connected to a conductor of resistance R Case Study Question CBSE Board 2023-24

When the terminals of a cell are connected to a conductor

#### (i) Choose the incorrect statement :

1. The potential difference (V) between the two terminals of a cell in a closed circuit is always less than its emf ( Îµ, during discharge of the cell.
2. The internal resistance of a cell decreases with the decrease in temperature of the electrolyte.
3. When current is drawn from the cell then V=Îµâˆ’Ir.
4. The graph between potential difference between the two terminals of the cell (V) and the current (I) through it is a straight line with a negative slope

Correct answer (b) The internal resistance of a cell decreases with the decrease in temperature of the electrolyte.

Explanation: this statement is incorrect because internal resistance of a cell decrease with increase in temperature of electrolyte.

### (ii) Two cells of emfs 2.0 V & internal Resistance 0.1 Î© & 0.4 Î© respectively, are connected in Parallel. The equivalent emf of the combination will be:

(a) 2.0 V (b) 2.8 V (c) 6.0 V (d) 8.0 V

Ans: (b) 2.8 V

### (iv) (a) Five identical cells each of emf 2 Volt and internal resistance 0.1ohm are connected in Parallel. This combination in turn is connected to an external resistor of 9.98 ohm. The Current flowing through the resistor is:

(a) 0.05 A (b)0.1 A (c) 0.15 A (d) 0.2 A

Correct Answer : (d) 0.2 A

Or

#### (b) Potential difference across a cell in the open circuit is 6 Volt. It becomes 4 V when a current of 2 A is drawn from it. The internal resistance of the cell is:

(a) 1.0 Ohm (b) 1.5 Ohm (c) 2.0 ohm (d) 2.5 ohm