If radius of the solid sphere is doubled by keeping its mass constant, the ratio of their moment of inertia about any of its diameter is

For a metallic wire, the ratio of voltage to corresponding current is

In air, a charged soap bubble of radius ' $R$ ' breaks into 27 small soap bubbles of equal radius ' $r$ '. Then the ratio of mechanical force acting per unit area of big soap bubble to that of a small soap bubble is

Two parallel conductors carrying unequal currents in the same direction ............