Gravity

Understanding gravitational forces, orbits, and celestial mechanics

Topics

How does gravity affect objects?

Gravity affects objects by pulling them toward each other with a force proportional to their masses and inversely proportional to the square of the distance between them. This causes objects to accelerate, fall, and orbit.

How does the moon affect tides?

The Moon affects tides through its gravitational pull on Earth's oceans. The Moon's gravity is stronger on the side of Earth facing the Moon, pulling water toward it and creating high tides. The Sun also contributes to tides.

What is escape velocity?

Escape velocity is the minimum speed an object needs to escape a planet's or moon's gravitational pull without further propulsion. For Earth, escape velocity is approximately 11.2 kilometers per second.

Why do planets orbit the sun?

Planets orbit the Sun because the Sun's gravity pulls them inward while their forward motion carries them forward. These two forces balance, creating a stable elliptical orbit instead of planets falling into or flying away from the Sun.

Why is gravity weaker on the moon?

Gravity is weaker on the Moon because the Moon has less mass than Earth. Since gravitational force depends on mass, the Moon's smaller mass creates a gravitational field about one-sixth as strong as Earth's.