All the known planets move in
- elliptical path
- straight path
- hyperbolic path
- circular path
The Correct Option is A
Solution and Explanation
All the planets move in an elliptical path. The speed of the planets moving in an elliptical path varies according to their position. For example, Moon is the natural satellite of the earth that revolves around the earth in an elliptical path. When moon is away from the earth, it moves slowly but the speed of the moon becomes faster when it is at the closest position to the earth.
The size of the ellipse is measured with the help of the major and minor axis.
- Major Axis - It is the longest distance.
- Minor Axis - It is the shortest distance.
Elliptical orbits also offers an advantage to communication satellite by making them visible to a ground station for a longer period of time.
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Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : 02 is liberated in the non-cyclic photophosphorylation.
Reason (R) : Liberation of oxygen is due to photolysis of water.
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- cloning
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : The Cro-Magnon man was the direct ancestor of the living modern man.
Reason (R) : Cro-Magnon man had slightly prognathous face.
In the light of the above statements, choose the correct answer from the options given below
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Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A) : In eukaryotes, transcription occurs in nucleus.
Reason (R) : In bacteria, transcription and translation occurs in cytoplasm.
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- Transcription
- Which of the following salts is coloured salt before heating?
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- d -and f -Block Elements
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].