If each resistance in the figure is of $9\,\Omega$,then the reading of the ammeter is ............ $A$.

$A$ battery consisting of $6$ cells,each with an internal resistance of $0.5\, \Omega$ and an $e.m.f.$ of $2\, V$,is being charged by a $220\, V$ $D.C.$ mains using an external resistor of $10\, \Omega$. The charging current is: (in $, A$)

$A$ fuse wire of radius $0.2 \,mm$ blows off with a current of $5 \,A$. The fuse wire of the same material but of radius $0.3 \,mm$ will blow off with a current of:

The internal resistances of two cells shown in the figure are $0.1\,\Omega$ and $0.3\,\Omega$. If $R = 0.2\,\Omega$,find the potential difference across the cells.

If two bulbs of wattage $25\, W$ and $100\, W$ respectively,each rated at $220\, V$,are connected in series with a supply of $440\, V$,then which bulb will fuse?

Two batteries $A$ and $B$, each of e.m.f. $2 \, V$, are connected in series to an external resistance $R = 1 \, \Omega$. If the internal resistance of battery $A$ is $1.9 \, \Omega$ and that of $B$ is $0.9 \, \Omega$, what is the potential difference between the terminals of battery $A$?