A physical quantity varies inversely as another quantity squared.
Law of Universal Gravitation
For any pair of objects, each object attracts the other object with a force that is directly proportional to the product of the masses of the objects, and inversely proportional to the square of the distance between their centers of mass
The deviation of an orbiting object from its path around the center of force caused by the action of an additional center of force
Universal Gravitational Constant, G
measures the strength of gravity
A mass that has collapsed to so great a density that its enormous local gravitational field prevents light from escaping
That which exists in the space surrounding a mass, electric charge, or magnet, so that another mass, electric charge, or magnet introduced to this region will experience a force. Examples of force fields are gravitational fields, electric fields, and magnetic fields.
A force field that exists in the space around every mass or group of masses
The cutoff of light from the full moon when Earth is directly between the sun and the moon, so that the Earth's shadow is cast by the moon
A tide that occurs when the moon is halfway between a new moon and a full moon, in either direction. The tides due to the sun and the moon partly cancel, so that the high tides are lower than average and the low tides are not as low as average
The cutoff of light from the sun to an observer on Earth when the moon is directly between the sun and Earth
A high of a low tide that occurs when the sun, Earth, and moon are all lined up so that the tides due to the sun and moon coincide, making the high tides higher than average and the low tides lower than average
The condition of free fall toward or around Earth, in which an object experiences no support force