Background
Newton’s law of gravity states that every object attracts every other object in the universe. This attraction between any two objects is a function of mass of the objects and the distance between them. Gravitational force of attraction between two objects is directly proportional to the product of the mass of the objects and inversely proportional to the square of the distance between them. In other words, as the mass of the objects increase, with everything else remaining constant, gravitational force of attraction increases. If however, the distance between them increases with everything else being constant, then gravitational force of attraction decreases.
The Discrepant Event: Gravity and The Moon
The sun, the moon and the Earth are all linked by gravity. The sun pulls more than twice as hard as the Earth. But every night you see the moon rise up in the sky without flying off to be with the sun. Even on a day when the three are perfectly aligned with the moon in between the two, it still does not fly off. Why?
Concepts involved:
- law of gravity, mass, distance.
