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प्रश्न
Answer the following question in detail.
State Kepler’s three laws of planetary motion.
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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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- only the third law will be valid.
- the second law will not change.
- the first law will still be valid.
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- all three of Kepler’s laws would still be valid.
- only the third law will be valid.
- the second law will not change.
- the first law will still be valid.
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[G = 6.67 × 10–11 SI units and M = 6 × 1024 kg]
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