# Circular and Satellite Motion - Mission CG6 Detailed Help

 There is much talk about Isaac Newton's law of universal gravitation and the falling apple. The significance of the apple was that Newton ____.
 Newton's Law of Universal Gravitation: All objects with mass attract each other with a gravitational force. The magnitude of the force is directly related to the product of the masses and inversely related to the square of the separation distance between their centers.
 Newton's proposal of the law of universal gravitation was based upon the apple and the moon argument. In his day, scientists largely believed that there were physical laws that governed the motion of objects on Earth and a different set of physical laws which governed the motion of objects in the heavens. Newton challenged this theory, arguing that the force that caused an apple to fall to Earth also caused the moon to orbit the Earth. Newton proposed that the moon orbited the Earth due to the force of gravity. Newton compared the distance of the moon to Earth's center to the distance of the apple to Earth's center. He also compared the acceleration of the moon to that of the apple. He observed that the ratio of the acceleration of the apple to that of the moon was inversely related to the square of the distances which separated them from Earth's center. He argued that the force of gravity caused each to accelerate towards Earth's center. This formed the basis of much of his theory.