Most common factors that affect gravity are mass of the body, distance from centers, shape of bodies,etc. Gravity is a binding force, always acting to bind any material closure and closure inwards. If we think this way, then gravity is maximum at its centre and decreases slowly away from its centre.

In the case of gravity, mediated by spin 2 particles, charge is mass, which is always positive. Thus, q1q2 is always greater than zero, and gravity is always attractive. For spin 0 force mediators, however, there is no restriction on the charges and you can very well have repulsive forces.

Aside from the long-running Anti Gravity column in Scientific American, however, there is no such thing as antigravity. Only way out in deep space, beyond the domain of any planets or stars, can you truly escape gravity. As of yet, no technology exists to neutralize the pull of gravity.

The Zero Gravity Research Facility is NASA’s premier facility for ground based microgravity research, and the largest facility of its kind in the world. The Zero-G facility is one of two drop towers located at the NASA site in Brook Park, Ohio. The Zero-G facility has been operational since 1966.

Force is defined as a push or pull acting on an object. Forces include gravity, friction, and applied force. Force causes changes in the speed or direction of motion. These changes are called acceleration.

For example, when a book is placed on a table, the normal force keeps the book from falling through the table. Gravity is pulling the book downward, but since the book isn’t actually falling, something must be pushing it up. This force is called the normal force.

gravity