How is a voltmeter connected in a circuit?

$(i)$ Name and state the law that gives the relationship between the current through a conductor and the potential difference across its two terminals. Also,express this law mathematically.
$(ii)$ Draw the $V-I$ graph for this law. Justify your answer.
$(iii)$ Write the name and use of the circuit components whose symbols are given below:
$(a)$ $A$ resistor with an arrow through it.
$(b)$ $A$ circle with a dot inside,connected to two lines.

What is the equivalent resistance of resistors $R_{1}$ and $R_{2}$ connected in parallel connection?

$(a)$ $(i)$ What is meant by saying that the potential difference between two points is $1 \, V$? $(ii)$ How much energy is given to $5 \, C$ of charge passing through a $12 \, V$ battery? $(b)$ Describe an activity with a necessary electric circuit to study the factors on which the resistance of a conducting wire depends.

Why do we use copper and aluminium wire for the transmission of electric current?

$(a)$ Derive the formula for the calculation of work done when current flows through a resistor.
$(b)$ One electric bulb is rated $40 \ W$ and $240 \ V$ and another is $25 \ W$ and $240 \ V$. Which bulb has higher resistance and how many times?