Question
State Kepler’s three laws of planetary motion.
✓
Answer
- All planets move in elliptical orbits around the Sun with the Sun at one of the foci of the ellipse.
- The line that joins a planet and the Sun sweeps equal areas in equal intervals of time.
- 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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ii. 1057 MHz (frequency of radiation arising from two close energy levels in hydrogen known as Lamb Shift).
iii. 5890 A – 5896 A [double lines of sodium]
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