What is the $SI$ unit of electric charge?

An electric kettle consumes $1\, kW$ of electric power when operated at $220\, V$. $A$ fuse wire of what rating (in $A$) must be used for it?

$(a)$ Name the instrument/device used to measure electric current in a circuit.
$(b)$ How is an ammeter connected in a circuit to measure current flowing through it?

Who invented the simple battery?

The following table provides the resistivity of three samples:

Sample	$A$	$B$	$C$
Resistivity	$1.6 \times 10^{-8} \Omega \cdot m$	$5.2 \times 10^{-8} \Omega \cdot m$	$100 \times 10^{-6} \Omega \cdot m$

Which of them is suitable for heating elements of electrical appliances and why?

$(a)$ Explain how a cell maintains current in a circuit.
$(b)$ In the circuit given below,the resistance of the path $xTy = 2 \, \Omega$ and that of $xZy = 6 \, \Omega$.
$(i)$ Find the equivalent resistance between $x$ and $y$.
$(ii)$ Find the current in the main circuit.
$(iii)$ Calculate the current that flows through the path $xTy$ and $xZy$.