Gravity or gravitation, is a natural phenomenon by which all things with mass or energy are brought toward (or gravitate toward) one another. On Earth, gravity gives weight to physical objects. Gravity has an infinite range, although its effects become weaker as objects get further away. Here are some interesting properties of gravity given in the answers of the quiz:
1. The gravity exert the same force on objects regardless of their mass. The only thing that can change the falling speed is the resistance of the fluid (or the air) they fall trough. But the height is not that big to allow friction to slow down the objects, so they all will hit the ground at the same time.
2. The bag will accelerate its speed untill it reaches a Terminal velocity. As the speed of an object increases, so does the drag force acting on it, which also depends on the substance it is passing through, for example air. At some speed, the force of resistance(drag force) will equal the gravitational pull on the object. At this point the object stops accelerating and continues falling at a constant speed called the terminal velocity.
3. The force of gravity changes with altitude. So the kid on mount Everest will weight approx 0.03 kg. less. But it also changes when going to the center of the earth. That means the kid deep underground will also weight less, becauce she experience gravity from all directions. If we reach the center of the earth we will actualy weight 0 kg.