A small block of mass $100 \mathrm{~g}$ is tied to a spring of spring constant $7.5 \mathrm{~N} / \mathrm{m}$ and length $20 \mathrm{~cm}$. The other end of spring is fixed at a particular point A. If the block moves in a circular path on a smooth horizontal surface with constant angular velocity $5 ~\mathrm{rad} / \mathrm{s}$ about point $\mathrm{A}$, then tension in the spring is -