An electric iron draws a current of $0.5\, A$ when the voltage is $200\, V$. Calculate the amount of electric charge flowing through it in one hour. (in $C$)

State with the help of a circuit diagram an activity to find the resistance $R$ of a given wire. $A$ current of $0.2 \, A$ passes through a resistor of $20 \, \Omega$. Find the potential difference across its ends.

$B_{1}$,$B_{2}$ and $B_{3}$ are three identical bulbs connected as shown in the figure. When all the three bulbs glow,a current of $3 \, A$ is recorded by the ammeter $A$.
$(i)$ What happens to the glow of the other two bulbs when the bulb $B_{1}$ gets fused?
$(ii)$ What happens to the reading of $A_{1}$,$A_{2}$,$A_{3}$ and $A$ when the bulb $B_{2}$ gets fused?

What is the process of depositing a layer of gold on silver called?

An electric iron has a rating of $750\, W; 200\, V$. Calculate:
$(i)$ The current required.
$(ii)$ The resistance of its heating element.
$(iii)$ Energy consumed by the iron in $2$ hours.

Draw a circuit diagram for a circuit consisting of a battery of five cells of $2 \text{ V}$ each, a $5 \, \Omega$ resistor, a $10 \, \Omega$ resistor, and a $15 \, \Omega$ resistor, an ammeter, and a plug key; all connected in series. Also, connect a voltmeter to record the potential difference across the $15 \, \Omega$ resistor and calculate:
$(i)$ the electric current passing through the above circuit and
$(ii)$ the potential difference across the $5 \, \Omega$ resistor when the key is closed.