-Weightlessness, condition experienced while in free-fall, in which the effect of gravity is canceled by the inertial force resulting from orbital flight. The term zero gravity is often used to describe such a condition.
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-Weightlessness is a situation in which the effective weight of the body becomes zero. Example 01: When a body is lying in a freely falling lift, then acceleration, a = g. So, the effective acceleration due to gravity in the left. g'=g–a⇒g'=g−g=0.
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-Weightlessness is the complete or near-complete absence of the sensation of weight. This is also termed zero-G, although the more correct term is "zero G-force". It occurs in the absence of any contact forces upon objects including the human body.
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-The sensation of weightlessness, or zero gravity, happens when the effects of gravity are not felt. Technically speaking, gravity does exist everywhere in the universe because it is defined as the force that attracts two bodies to each other. But astronauts in space usually do not feel its effects.
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-Weightlessness of a body is the state in which the body experiences that the body is not being attracted by any force.
