Write Joule's law of heating.
The resistance of one conducting wire is $10\, \Omega$. If battery of $1.5\, V$ is connected to it, then how much electric current will flow through it?
How much current will an electric bulb of resistance $1100\, \Omega$ draw from a $220\, V$ source $?$ If $a$ heater of resistance $100\, \Omega$ is connected to the same source instead of the bulb, calculate the current drawn by the heater.
Study the $V - I$ graph for a resistor as shown in the figure and prepare a table showing the values of $I$ (in amperes) corresponding to four different values of $V$ (in volts). Find the value of current $I$ (amperes) for $V=10$ volts. How can we determine the resistance of the resistor from this graph ?
What is the lowest resistance that can be obtained by combining four coils of resistances $4\, \Omega, 8\, \Omega, 12\, \Omega$ and $24\, \Omega ?$