Explain why it isn't safe for a bus to carry standing passengers on the upper Decker
Gravity is the force that gives weight to objects and causes them to fall to the ground when dropped.
Two major factors, mass and distance, affect the strength of gravitational force on an object.
The center of gravity (CG) of an object is the point at which weight is evenly dispersed and all sides are in balance.
A human's center of gravity can change as he takes on different positions, but in many other objects, it's a fixed location.