Explain how inertia and gravity combine to keep earth in its orbit.

The law of gravity valid on earth is applicable in the movement of celestial bodies. Newton came to this conclusion and explained this by his law of motion. The gravitational force attracts the bodies and keeps them moving on certain paths, also, with the help of the force of inertia. All celestial bodies, and so on the earth in the solar system, move along their orbits at a certain speed around the sun. What attracts the earth and other planets to the sun is the force of gravity. Due to its speed in the movements of the earth, it is influenced by the force of inertia, which always seeks to maintain the state of the body. In other words, the earth is attracted to the sun by the force of gravity, and it would be drawn much closer, so that the earth leaves its orbit, if there were no force of inertia. The force of inertia tends to hold the earth in motion, but due to the force of gravity, this movement is not arbitrarily in the cosmos, but always along the path determined by the combination of two forces: gravity and inertia.

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