Define the unit of electric current.

Let the resistance of an electrical component remain constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?

Name a device that helps to maintain a potential difference across a conductor.

Why does the cord of an electric heater not glow while the heating element does?

What is meant by saying that the potential difference between two points is $1$ $V$?

How can three resistors of resistances $2\, \Omega$,$3\, \Omega$,and $6\, \Omega$ be connected to give a total resistance of $1\, \Omega$?