{"id":261,"date":"2016-11-23T14:08:27","date_gmt":"2016-11-23T14:08:27","guid":{"rendered":"http:\/\/www.experimentoscientificos.es\/?p=261"},"modified":"2018-02-17T11:39:32","modified_gmt":"2018-02-17T11:39:32","slug":"leyes-kepler","status":"publish","type":"page","link":"https:\/\/www.experimentoscientificos.es\/en\/leyes-kepler\/","title":{"rendered":"Kepler's Laws"},"content":{"rendered":"
Kepler was a German scientist, born in the 16th century (1571), who formulated the three laws describing the motions of the planets, including those of the planets. earth movements<\/a>. At the time Kepler brought out the 3 laws<\/strong>Newton's Law of Gravitation was not yet known (he relied heavily on Kepler's Laws), and the orbits of the planets were believed to be circular.<\/p>\n For the formulation of these three laws, Kepler based himself on what was known to date, and on observations of the various positions of the planets. He collaborated with the imperial astronomer Tycho Brahe, and it was not until Brahe's death that he had access to all his previous observations.<\/p>\n The keple's laws<\/strong>r are defined for the motion of the planets around the Sun, but they can also be applied to the motion of the satellites around the planets. For example of the Moon around the Earth.<\/p>\n All the planets move around the Sun in elliptical orbits.<\/p>\n This first law of orbits<\/strong> indicates that the motion of the planets is not circular around the sun, but elliptical. The sun is at one of the foci of the ellipse. Therefore the Earth is sometimes further away from the Sun, sometimes closer to it. From this first law we derive the other two laws that define some of the characteristics of this elliptical motion.<\/p>\n Interestingly, the seasons (summer, winter...) do not depend on the distance of the Earth from the Sun, but on the tilt of the Earth on its axis. This fact, as well as the definition of the equinoxes and solstices (which are defined by the distance of the Earth to the Sun) is more detailed in the section on the earth movements<\/a>.<\/p>\n The knowledge that the motion of the planets was not circular, but elliptical, was a great frustration to Kepler<\/strong>who was a great believer and did not understand why God had not chosen a simple trajectory for the planets.<\/p>\n<\/div>\n A line drawn between a planet and the sun sweeps equal areas in equal times.<\/p>\n This second law implies that the time to travel the distance A1 is the same as the time to travel the distance A2, and therefore the speed of the Earth around the Sun is not constant. The velocity will be greater the further away the Earth is from the Sun.<\/p>\n This second law corresponds today to the conservation of angular momentum<\/strong>r or kinetic momentum of Newton<\/a>. At the level of the motion of the earth (and the planets in general) around the sun it is very interesting, as it indicates that the velocity in the\u00a0translation movement of the earth\u00a0<\/a>around the sun is not constant, but is greatest at aphelion (the closer it is to the sun) and smallest at perihelion.<\/p>\n<\/div>\n The square of the orbital period of any planet is proportional to the cube of the semi-major axis of its orbit. The orbital period is the time it takes for a planet to go around the Sun.<\/p>\n This law is known as Kepler's constant. This third law defines that the orbital period is directly proportional to the cube of the length of the semi-major axis of its elliptical orbit. The relationship between the two corresponds to a constant. It corresponds to the following formula, where T is the orbital period and r is the length of the semi-major axis of its orbit.<\/p>\n<\/div>\n Kepler's third law relates the distance of a planet from the Sun to how long it will take to go around the Sun. The closer the planet is to the Sun, the less time it will take to go around the Sun.<\/p>\n This law was a spectacular discovery, as it related the trajectories of the planets to each other. It is also valid for other objects with gravitational motion, such as the motion between the Earth and the Moon.<\/p>\n<\/div>\nSTATEMENT OF KEPLER'S 3 LAWS<\/h2>\n
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FIRST: LAW OF ORBITS<\/h2>\n
SECOND: LAW OF THE AREAS<\/h2>\n
THIRD: LAW OF PERIODS<\/h2>\n
REALISATION OF KEPLER'S AND NEWTON'S LAWS<\/h2>\n