The radius of the earth is 6400 km and $g=10ms^{-2}$. In order that a body of 5 kg weights zero at the equator, the angular speed of the earth is = rad/sec
for condition of weight lessness at equator $ \omega = \sqrt { g / R } $ $ = \sqrt { 10 \over 6400 \times 10^3 } = { 1 \over 800} rad /sec $