A geostationary satellite orbits around the earth in a circular orbit of radius $36,000\, km$. Then, the time period of a spy satellite orbiting a few hundred km above the earth's surface $ (R_ e = 6400km) $ will approximately be
- 1/2 h
- 1h
- 2h
- 4h
The Correct Option is C
Solution and Explanation
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Concepts Used:
Gravitation
In mechanics, the universal force of attraction acting between all matter is known as Gravity, also called gravitation, . It is the weakest known force in nature.
Newton’s Law of Gravitation
According to Newton’s law of gravitation, “Every particle in the universe attracts every other particle with a force whose magnitude is,
- F ∝ (M1M2) . . . . (1)
- (F ∝ 1/r2) . . . . (2)
On combining equations (1) and (2) we get,
F ∝ M1M2/r2
F = G × [M1M2]/r2 . . . . (7)
Or, f(r) = GM1M2/r2
The dimension formula of G is [M-1L3T-2].