Under the following conditions, the weight of a person can become zero :
(i) At the centre of Earth, the value of `g` is zero, so weight of a person `(= mg)` is zero.
(ii) At the null points in space, the resultant gravitational force due to difference masses cancel out, hence weight of a person is zero there.
(iii) In a frelly falling lift, the apparent weight of a person becomes zero.
(iv) In a satellite orbiting around Earth, the weight of a person is zero, due to weightless state inside the satellite.