List any two factors on which the resistance of a conductor depends.

Why do the wires connecting an electric heater to the mains not glow while its heating element does?

You are given three resistors of $10\, \Omega, 10\, \Omega, 20\, \Omega$,a battery of emf $2.5\, V$,a key,an ammeter,and a voltmeter. Draw a circuit diagram showing the correct connections of the given components such that the voltmeter gives a reading of $2.0\, V$.

The $SI$ unit of electric charge is $.........$

Read the following statements carefully and state whether each statement is true or false:
$(i)$ The quantity of charge flowing past a point multiplied by time is current.
$(ii)$ The flow of charge through a conducting wire connected to a cell is the result of a chemical reaction inside the cell.
$(iii)$ The resistivity of all pure metals increases with an increase in temperature.
$(iv)$ Ohm's law is a relation between the power used in a circuit to the current and the potential difference.
$(v)$ $A$ series circuit has only one conducting path for the electrons that move through it; a parallel circuit has multiple conducting paths.
$(vi)$ $A$ conducting wire offers resistance to the flow of electrons because electrons repel each other in the wire.

The equivalent resistance between points $A$ and $B$ in the following electric circuit is: