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प्रश्न
Answer the following question in detail.
State Kepler’s three laws of planetary motion.
उत्तर
1. Kepler’s law of orbits:
Statement:
All planets move in elliptical orbits around the Sun with the Sun at one of the foci of the ellipse.
2. Kepler’s law of equal areas:
Statement:
The line that joins a planet and the Sun sweeps equal areas in equal intervals of time.
3. Kepler’s law of periods:
Statement:
The square of the time period of revolution of a planet around the Sun is proportional to the cube of the semimajor axis of the ellipse traced by the planet.
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Observe the given figure and answer these following questions.
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- Explain the relation between areas ASB, CSD and ESF.
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If the distance between the sun and the earth is made three times, then attraction between the two will ______
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The mass and radius of earth is 'Me' and 'Re' respectively and that of moon is 'Mm' and 'Rm' respectively. The distance between the centre of the earth and that of moon is 'D'. The minimum speed required for a body (mass 'm') to project from a point midway between their centres to escape to infinity is ______.
A planet revolves in an elliptical orbit around the sun. The semi-major and minor axes are a and b, then the time period is given by:
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- the second law will not change.
- the first law will still be valid.
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- the second law will not change.
- the first law will still be valid.
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- to follow a trajectory such that the areal velocity is constant.
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