In the given circuit,if the measuring instruments are ideal,then the reading of ammeter $A_1$ is:

$A$ uniform metallic wire having resistance $4 \ \Omega$ is bent to form a square loop $(ABCD)$ (see figure). $A$ resistance of $2 \ \Omega$ is connected between points $B$ and $D$ and a battery of $2 \ V$ is connected across points $A$ and $C$ as shown in the figure. Now the value of current $(I)$ is: (in $A$)

The total current supplied to the circuit by the battery is ............. $A$.

$A$ battery of internal resistance $4 \,\Omega$ is connected to the network of resistances as shown. In order to give the maximum power to the network,the value of $R$ (in $\Omega$) should be

In the given circuit,the value of $\left|\frac{I_1+I_3}{I_2}\right|$ is

If the mass deposited in $30 \ s$ is $m$,what will be the $E.C.E$ of the copper voltameter?