Kirchhoff's second law is based on the law of conservation of:

The figure shows a network of currents. The values of the currents are shown in the figure. What is the value of current $I$ in $A$?

The figure shows a part of an electric circuit. The potentials at points $a$,$b$,and $c$ are $30\,V$,$12\,V$,and $2\,V$ respectively. The current through the $20\,\Omega$ resistor will be $........\,A$.

Five conductors meet at a point $x$ as shown in the figure. What is the current flowing through the fifth conductor?

In the circuit given,the correct relation for a balanced Wheatstone bridge is

The galvanometer has no deflection and the length of wire $AB$ is $350 \, cm$. Then $AC$ equals to ............... $cm$.