A metal cube of side `10 cm` is subjected to a shear stress `10^4 N/m^2`. Calculate the rigidity modulus, if the top of the cube is displaced by `0.05 cm` with respect to its bottom.

A regular hexagon of side 10 cm has a charge 5 muC at each of its vertices. Calculate the potential at the centre of the hexagon.

2 xx 10^8' atoms of carbon are arranged side by side. Calculate the radius of carbon atom if the length of this arrangement is '2.4 cm .'

The resistance of a 0.5 N solution of salt is 20 Omega .Calculate the equivalent conductance of the solution if the platinum electrodes are 1.5 cm apart and each having an area of 3.0cm^(2) .