$n$ equal resistors are first connected in series and then connected in parallel. The ratio of the maximum to the minimum resistance is

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 table given below provides the resistivity of three samples in $\Omega \cdot m$:

Sample	Resistivity $(\Omega \cdot m)$
$A$	$1.6 \times 10^{-8}$
$B$	$7.5 \times 10^{17}$
$C$	$44 \times 10^{-6}$

$(a)$ Which of them is a good conductor? Which is an insulator? Why?
$(b)$ $A$ wire of resistance $4 \ \Omega$ is folded on itself to double its thickness. Calculate the new resistance of the wire.

Three $V-I$ graphs are drawn individually for two resistors and their series combination. Out of $A, B, C$,which one represents the graph for the series combination of the other two? Give a reason for your answer.

What is the power of a bulb rated at $2.5 \, V$ and $500 \, mA$ (in $, W$)?

$(a)$ Define the term 'volt'.
$(b)$ State the relation between work,charge,and potential difference for an electric circuit. Calculate the potential difference between the two terminals of a battery,if $100 \ J$ of work is required to transfer $20 \ C$ of charge from one terminal of the battery to the other.