The flow of charge through a conducting wire connected to a cell is the result of chemical reaction inside the cell.

Define $1$ volt.

In an experimental set-up as shown below,a piece of silver was placed touching points $A$ and $B$. Next time it was replaced by a piece of wood. In which case did the bulb glow? Give reason to justify the observation.

What is the cause of resistance?

Define one watt.

If the diameter of a conducting wire is doubled,how many times does its resistance become?