Compute how long would day on Earth have to be in order to cause weightlessness at the equator. The Earth's radius is R = 6,400 km, its mass is M = 6·10²⁴ kg, the gravitational constant is G = 6.7·10⁻¹¹ kg⁻¹·m³·s⁻². Assume the Earth to be spherical. Mirek was sitting by the window watching time fly.