Deduce an expression for the internal resistance of the cell.

The p.d. between the two terminals of a cell in open circuit is 2 volt. The p.d. falls to 1.5 volts when the cell is connected across a 2 ohm resistance. Find the internal resistance of the cell.

Deduce the expression for energy density.

What is the potential difference between two terminals of cell of emf of 6V in the open circuit ? Neglect the internal resistance of the cell.

Deduce an expression for the range of a projectile. For the given velocity of projection when is this maximum ?