IMPORTANT QUESTIONS

How does the heat produce in a wire of a conductor depend upon the current passing through the conductor? 

How does the heat produced in a wire of a conductor depend upon the resistance of the conductor? 

Name the physical quantity that is measured in kilowatt. (Electric energy/ Electric power).

Name the physical quantity that is measured in kilowatt-hour.
(Choose from: electric power / electrical energy)

State Ohm’s law and write its mathematical form. 

Three resistances $R_1, R_2$ and $R_3$ are connected in series. Draw a circuit diagram and derive an expression for the equivalent resistance of the combination.

 Three resistances $R_1, R_2$ and $R_3$ are connected in parallel. Draw a circuit diagram and derive an expression for the equivalent resistance of the combination.

Define electric power. State its unit and derive an expression relating it with $V$, $R$ and $I$.