Two electric bulbs ($60\,W$ and $100\,W$ respectively) are connected in series. The current passing through them is

The ratio of the equivalent resistance of the network (shown in figure) between the points $a$ and $b$ when the switch is open and when the switch is closed is $x : 8$. The value of $x$ is ..... .

What equal length of an iron wire and a copper-nickel alloy wire, each of $2 \; mm$ diameter, connected in parallel, gives an equivalent resistance of $3 \; \Omega$? (Given: resistivities of iron and copper-nickel alloy wire are $12 \; \mu\Omega \cdot cm$ and $51 \; \mu\Omega \cdot cm$ respectively) (in $m$)

$A$ wire with a resistance of $0.5 \, \Omega \, m^{-1}$ is bent into a circle of radius $1 \, m$. $A$ similar wire is connected across its diameter. What is the equivalent resistance between the two ends of the diameter?

The resistance between points $A$ and $C$ in the given network is

The reading of the ammeter in the following circuit is ................... $A$ (Assuming an ideal ammeter).