Internal Resistance of a Cell

A battery of e.m.f. 6.0 V supplies current through a circuit in which the resistance can be changed. A high resistance voltmeter is connected across the battery. When the current is 3 A, the voltmeter reads 5.4 V. Find the internal resistance of the battery.

Name two factors on which the internal resistance of a cell depends and state how does it depend on the factors stated by you.

A cell of e.m.f. 1.8V and internal resistance 2Ω is connected in series with an ammeter of resistance 0.7Ω and a resistor of 4.5Ω as shown in Fig. 

1. What would be the reading of the ammeter?
2. What is the potential difference across the terminals of the cell? 

A battery of 4 cell, each of e.m.f. 1.5 volt and internal resistance 0.5 Ω is connected to three resistances as shown in the figure. Calculate:
(i) The total resistance of the circuit.
(ii) The current through the cell.
(iii) The current through each resistance.
(iv) The p.d. across each resistance.

A cell of Emf 2 V and internal resistance 1.2 Ω is connected with an ammeter of resistance 0.8 Ω and two resistors of 4.5 Ω and 9 Ω as shown in the diagram below:

1) What would be the reading on the Ammeter?

2) What is the potential difference across the terminals of the cell?

A cell supplies a current of 0.6 A through a 2Ω coil and a current of 0.3 A through on 8Ω coil. Calculate the e.m.f and internal resistance of the cell.

A cell of e.m.f ε and internal resistance r is used to send current to an external resistance R. Write expressions for

1. the total resistance of circuit.
2. the current drawn from the cell.
3. the p.d. across the cell.
4. voltage drop inside the cell. 

What happens to the resistivity of semiconductor with the increase of temperature?