SCIENCE
ENVIRONMENTAL SCIENCES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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An elliptical orbit around the moon.
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An elliptical orbit around the Sun.
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A circular orbit around the moon.
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A circular orbit around the Sun.
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Detailed explanation-1: -Kepler’s First Law: each planet’s orbit about the Sun is an ellipse.
Detailed explanation-2: -The first reason has to do with the fact that the Earth’s orbit is not a perfect circle, but is elliptical with the Sun being nearer one end of the ellipse. The speed of the Earth in this elliptical orbit varies from a minimum at the farthest distance to a maximum at the closest distance of the Earth to the Sun.
Detailed explanation-3: -The elliptical orbits of planets were indicated by calculations of the orbit of Mars. From this, Kepler inferred that other bodies in the Solar System, including those farther away from the Sun, also have elliptical orbits.
Detailed explanation-4: -Orbits are eliptical because of Newtons Law of Gravity (bodies attract each other in proportion to their mass and inversly proportional to the square of the distance between them). All worked out by Kepler some years ago. A circular orbit is a special (and very unlikely) case of an eliptical orbit.
Detailed explanation-5: -But Kepler not only adamantly defended the idea that planets orbit the sun, he also revealed that their paths were not perfect circles. His descriptions of planetary motions became known as Kepler’s laws.