gravity

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Force of attraction that arises between objects by virtue of their masses. The larger the mass of an object the more strongly it attracts other objects. On Earth, gravity causes objects to have weight; it accelerates objects (at 9.806 metres per second per second/32.174 ft per second per second) towards the centre of the Earth.

The Earth's gravity also attracts the Moon towards the Earth, keeping the Moon in orbit around the Earth. The Moon's gravity is one-sixth that of Earth's, so objects on the Moon weigh less than on Earth. The Sun contains 99.8% of the mass of the Solar System, and the resulting large force of gravity keeps the planets of the Solar System in orbit around the Sun.

A spacecraft launched from Earth must overcome the force of gravity before entering space. This is achieved by using rocket boosters at various stages of the launch. The spacecraft needs an acceleration of three times that of gravity (3 g). The speed required to escape the Earth's gravitational field is 40,000 kph/25,000 mph.

Yellow represents the golden land of South America. Blue stands for the ocean separating the country from Spain. Red symbolizes the blood and courage of the people resisting the tyrants. Effective date: 26 November 1861. >>