Resistance of a material at 20^oC and 40^oC are 45 Ω and 85 Ω respectively. Find its temperature coefficient of resistivity.

Describe the microscopic model of current and obtain general form of Ohm’s law.

Obtain the macroscopic form of Ohm’s law from its microscopic form and discuss its limitation.

Explain the equivalent resistance of a series and parallel resistor network.

Explain the determination of the internal resistance of a cell using voltmeter.