Gravitational field
The gravitational field is a concept in physics that describes the influence or effect of a massive object on the space surrounding it. It's a way to quantitatively describe how gravity affects the space around a massive body and how other objects in that space will experience gravitational forces.
Here are some key points to understand about the gravitational field:
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Attractive Force: Gravitational fields are associated with massive objects, such as planets, stars, and other celestial bodies. These fields create a force that attracts other objects with mass towards the massive body. This force is the familiar force of gravity.
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Field Strength: The strength of the gravitational field at a particular point in space is a measure of the force per unit mass (newtons per kilogram or N/kg, equivalent to meters per second squared or m/s²). In other words, it tells you how much force a unit mass (1 kilogram) would experience due to gravity at that point.
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Direction: The gravitational field is a vector field, which means it has both magnitude and direction. The direction of the field points toward the massive object that creates it. For example, the gravitational field around the Earth points toward the Earth's center.
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Inverse Square Law: The strength of the gravitational field decreases with distance from the massive object following the inverse square law. This means that as you move farther from the massive object, the field strength diminishes according to the square of the distance.
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Superposition: If there are multiple massive objects in the vicinity, the gravitational fields they create add together through vector addition. This principle allows you to determine the net gravitational field at a point in space due to multiple sources of gravity.
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Units: Gravitational field strength is often measured in units of newtons per kilogram (N/kg) or meters per second squared (m/s²).