Gravity Gravitaional Force and its constant All explain
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Gravity is one of the four fundamental forces of nature. It is the force that causes objects with mass to attract each other. For example, the Earth attracts an apple, causing it to fall downward when dropped. This gravitational attraction exists between all objects that have mass, from the smallest particles to the largest celestial bodies.
Newton's Law of Universal Gravitation describes the gravitational force mathematically. The law states that the force equals G times the product of the two masses divided by the square of the distance between them. This means that larger masses create stronger gravitational forces, while greater distances result in weaker forces. The forces are equal and opposite, acting along the line connecting the centers of the two objects.
The gravitational constant G is a fundamental constant of nature with a value of approximately 6.674 times 10 to the negative 11 newton meters squared per kilogram squared. This constant is the same everywhere in the universe and determines how strong gravitational forces are. G is an extremely small number, which explains why gravity is the weakest of the four fundamental forces. It was first measured accurately by Henry Cavendish in 1798 using a torsion balance experiment.
The strength of gravitational force depends on two key factors: mass and distance. When the distance between objects doubles, the gravitational force becomes four times weaker, following an inverse square relationship. However, when the mass of either object doubles, the gravitational force doubles as well, showing a direct linear relationship. This is why the Moon, which is about 60 Earth radii away from Earth's center, experiences gravity that is 3600 times weaker than what we feel on Earth's surface.
To summarize what we have learned about gravity: Gravity is a fundamental force that causes attraction between all objects with mass. Newton's law of universal gravitation gives us the mathematical formula F equals G times m1 times m2 divided by r squared. The gravitational constant G is a universal value that determines the strength of this force. The force increases with larger masses but decreases rapidly with greater distances. Understanding gravity helps us explain everything from why objects fall to Earth to how planets orbit the Sun.