In the network shown in the figure,the potential difference across the $2R$ resistor is...... (The cell has an $emf$ $E$ and no internal resistance).

An ammeter and a voltmeter of resistance $R$ are connected in series to an electric cell of negligible internal resistance. Their readings are $A$ and $V$ respectively. If another resistance $R$ is connected in parallel with the voltmeter, what happens to the readings $A$ and $V$?

When a current of $4 \, A$ is passed through a cell for $2 \, minutes$,the mass deposited at the cathode is $m \, g$. If a current of $6 \, A$ is passed through the same cell for $40 \, seconds$,what mass will be deposited at the cathode?

An electric iron draws $5\, A$,a $TV$ set draws $3\, A$,and a refrigerator draws $2\, A$ from a $220\, V$ main line. The three appliances are connected in parallel. If all three are operating at the same time,the fuse used should be of ............. $A$. (in $, A$)

The resistance of a heater coil is $110\, \Omega$. $A$ resistance $R$ is connected in parallel with it,and the combination is joined in series with a resistance of $11\, \Omega$ to a $220\, V$ main line. The heater operates with a power of $110\, W$. The value of $R$ in $\Omega$ is

$A$ set of $n$ equal resistors,each of value $R$,are connected in series to a battery of emf $E$ and internal resistance $R$. The current drawn is $I$. Now,the $n$ resistors are connected in parallel to the same battery. The current drawn from the battery becomes $10I$. The value of $n$ is: