The slider provided on a rheostat changes the

Establish relation between potential difference $V$ and electric current $I$ by plotting graph.

Write Ohm's law.

Write the S.I. unit of resistivity. An electric motor takes $5 \mathrm{A}$ from a $220 \mathrm{V}$ source. Determine the power of the motor and energy consumed in $2$ hours.

The values of current ($I$) flowing through a given resistor of resistance ($R$), for the corresponding values of potential difference ($V$) across the resistor, are as given below:

Plot a graph between current ($I$) and potential difference ($V$) and determine the resistance ($R$) of the resistor.

A $V-I$ graph for a nichrome wire is given below. What do you infer from this graph? Draw a labelled circuit diagram to obtain such a graph.

Observe the correlation in the first pair and complete the second pair:
Resistor or resistance :  :: Rheostat : __________

On what factors does the resistance of a conductor depends?