$3$ identical bulbs are connected in series and these together dissipate a power $P$. If now the bulbs are connected in parallel,then the power dissipated will be

In an aluminium $(Al)$ bar of square cross-section,a square hole is drilled and is filled with iron $(Fe)$ as shown in the figure. The electrical resistivities of $Al$ and $Fe$ are $2.7 \times 10^{-8} \ \Omega m$ and $1.0 \times 10^{-7} \ \Omega m$,respectively. The electrical resistance between the two faces $P$ and $Q$ of the composite bar is

$A$ wire is broken into four equal parts. $A$ packet is formed by keeping the four wires together. The resistance of the packet in comparison to the resistance of the original wire will be:

In the arrangement of resistances shown below,the effective resistance between points $A$ and $B$ is ............... $\Omega$.

The current $I_{1}$ (in $A$) flowing through the $1\; \Omega$ resistor in the following circuit is:

Three resistors each of $4\,\Omega$ are connected together to form a network. The equivalent resistance of the network cannot be ............ $\Omega$.