What is potential difference? Is it a scalar quantity or a vector quantity? Give its $SI$ units.

$(a)$ Define potential difference between two points in a conductor.
$(b)$ Name the instrument used to measure the potential difference in a circuit. How is it connected?
$(c)$ $A$ current of $2 \, A$ passes through a circuit for $1$ minute. If the potential difference between the terminals of the circuit is $3 \, V$, what is the work done in transferring the charges?

How can we measure the potential difference across the ends of a conductor?

How is a voltmeter connected in a circuit?

Name a device that can be used to maintain a potential difference across a conductor. Also,draw its circuit symbol.

What is a voltmeter? How is it connected in a circuit?