The value of the resistance $R$ in the figure is .......... $\Omega$.

State the principle of a Wheatstone bridge.

The given figure shows a network of resistances and a battery. Identify the correct statement$(s)$.

The current through the wire $XY$ of the circuit shown is ................ $A$.

Consider the following statements regarding the network shown in the figure.
$(1)$ The equivalent resistance of the network between points $A$ and $B$ is independent of the value of $G$.
$(2)$ The equivalent resistance of the network between points $A$ and $B$ is $\frac{4}{3} R$.
$(3)$ The current through $G$ is zero.
Which of the above statements is/are true?

In the circuit shown in the figure,the current drawn from the battery is $4 \, A$. If the $10 \, \Omega$ resistor is replaced by a $20 \, \Omega$ resistor,then the current drawn from the circuit will be .............. $A$.