A body is rotating about its own axis. Its rotational kinetic energy is '$x$' and its angular momentum is '$y$'. Hence its moment of inertia about its own axis is

The percentage decrease in the weight of a body when taken to a height of $48$ km above the surface of the earth is (Radius of the earth is $6400$ km)

If $450$ erg of work is done in blowing a soap bubble of radius '$r$', the additional work required to be done to blow it to a radius equal to $3r$ is

The excess pressure inside a soap bubble of radius $2.5$ cm is $48$ dyne/cm$^2$. The surface tension of soap solution in dyne /cm is