What is the resistance of an ideal voltmeter?

The electrical resistivity of a few materials is given below in ohm-metre. Which of these materials can be used for making the element of a heating device?

$A$. $6.84 \times 10^{-8} \, \Omega m$

$B$. $1.60 \times 10^{-8} \, \Omega m$

$C$. $1.00 \times 10^{-4} \, \Omega m$

$D$. $2.50 \times 10^{12} \, \Omega m$

$E$. $4.40 \times 10^{-5} \, \Omega m$

$F$. $2.30 \times 10^{17} \, \Omega m$

The potential difference across the terminals of a cell is $1.5 \ V$. If it is connected with a resistance of $30 \ \Omega$,calculate the current flowing through the circuit. (in $A$)

Which effect of electric current is used in electroplating?

Why is parallel arrangement used in domestic wiring?

Which of the following statements is $NOT$ true for a series combination of two resistors?