The unit $Volt \times Ampere$ represents which physical quantity?

Why are alloys used to make standard resistors?

Mention the condition under which charges can move in a conductor. Name the device which is used to maintain this condition in an electric circuit.

$(a)$ For the circuit shown in the diagram,calculate:
$(i)$ The value of current through the $30\, \Omega$ resistor.
$(ii)$ The total resistance of the circuit.
$(b)$ Give two advantages of connecting electrical devices in parallel with a battery.

What is the unit of resistance?

Find the equivalent resistance across the two ends $A$ and $B$ of this circuit.