[Arkie2]

One G is level flight, what you experience sitting in your chair typing on your key board. Did you mean zero G?

[Young Werther]

An aircraft has an instrument called a "G meter" It measures the amount of force applied to the aircraft in "Gs". When you are flying straight and level, lift and gravity are in balance. When you initiate a climb the G meter will register the force being applied in positive Gs. When you initiate a dive a corresponding measurement in negative Gs will be registered. Therefore, a 1 G climb means that you are accelerating upward at twice the rate that gravity is pulling you downward. The same foces apply on a ferris wheel, roller coaster, and Whip the Whip.