CLASS 8 · LEARNING KNOWLEDGE
Kepler's laws as models – basic principles
How it works
Kepler's laws describe the motion of the planets around the Sun. First law: The planets move on elliptical orbits, with the Sun at one of the foci. Second law: The line connecting the Sun and the planet sweeps out equal areas in equal times. Third law: For planets orbiting the same central body, the ratio of the squares of their orbital periods is equal to the ratio of the third powers of their semi-major axes. These laws are models that help explain planetary motion in the solar system.
Note
Kepler's laws describe how planets move around the Sun: 1) elliptical orbits with the Sun at a focus, 2) area law for equal time intervals, 3) relationship between orbital period and orbit size.
Kepler's laws describe how planets move around the Sun: 1) elliptical orbits with the Sun at a focus, 2) area law for equal time intervals, 3) relationship between orbital period and orbit size.
An example
Which of Kepler's laws explains that a planet moves faster near the Sun than farther from the Sun?
The second Kepler's law explains this: In equal times, equal areas are swept out. Near the Sun, the planet must therefore cover a longer arc of its orbit in the same time and thus moves faster. (Answer: 2. law)
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50 Exercises
To the learning unit →Own explanation and own practice exercises by AmyMath. Subject reference framework: Astronomy. The topic assignment may vary by federal state.