Which has a greater resistance$-$a $100$ $W$ bulb or a $60$ $W$ bulb?

$(a)$ Name the effect of electric current which is utilised in the working of an electrical fuse.
$(b)$ How is a fuse connected in a domestic circuit?

Two conductors,one having resistance $R$ and another $2R$ are connected in turn across a $dc$ source. If the rate of heat produced in the two conductors is $Q_{1}$ and $Q_{2}$ respectively,what is the value of $Q_{1} / Q_{2}$?

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?

Tungsten is used almost exclusively for filaments of electric bulbs. List two reasons.

The unit $Joule/second$ $(J/s)$ is the unit of which of the following?