The radius of the earth is 6400 km and g 10 m/sec2. In order that a body of 5 kg weighs zero at the equator, the angular speed of the earth is

Q: The radius of the earth is 6400 km and g 10 m/sec2 . In order that a body of 5 kg weighs zero at the equator, the angular speed of the earth is

(a) 1/80 radian/sec

(b) 1/400 radian/sec

(c) 1/800 radian/sec

(d)1/1600 radian/sec

Ans: (c)