In a potentiometer experiment, the balancing length for a cell is $$240 \mathrm{~cm}$$. On shunting the cell with a resistance of $$2 \Omega$$, the balancing length becomes half the initial balancing length. The internal resistance of the cell is

Kirchhoff's current and voltage law are respectively based on the conservation of

In a wheatstone's bridge, three resistances $$\mathrm{P}, \mathrm{Q}$$ and $$\mathrm{R}$$ are connected in the three arms and the fourth arm is formed by two resistances $$S_1$$ and $$S_2$$ connected in parallel. The condition for the bridge to be balanced is

If a current flowing in a coil is reduced to half of its initial value, the relation between the new energy $$\left(E_2\right)$$ and the original energy $$\left(E_1\right)$$ stored in the coil will be