Question

Is law of Gravitation a universal law? How? ​

Answer 1

Yes , the law of Gravitation is a universal law because it is applicable to the entire universe .

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• Some more features of this law →

• It obeys the inverse square law
• It is a weak force .
• It is attractive in nature .

Answer 2

Question :

• Is law of Gravitation a Universal Law ? How ?

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Answer :

• Yes, Universal law is a Gravitational law.

• This law can be applicable for the whole universe such as it can be used to calcute the mass of planets and stars.

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Derivation :

• This law states that every particle of matter in this universe attracts every other particle with a force.

• This force is directly proportional to the product of their masses and inversely proportional to the square of the distance between the centres of these masses.

• The direction of the force acts along the line joining the masses.

• The force between the masses is always attractive and it does not depend on the medium where they are placed.

Let, $\bf{m_1 and\: m_2}$ be the masses of two bodies A and B placed r metre apart in space.

Force F ∝ $\bf{m_1 × m_2}$

F ∝ $\dfrac{1}{r²}$

• On combining the above two expressions

F ∝ $\dfrac{m_1 × m_2}{r²}$

F = $\dfrac{Gm_1 × m_2}{r²}$

• Where G is the universal gravitational constant.

Its value in SI unit is 6.674 × $\bf{10^-11}$ Nm²  $\bf{kg^-2}$

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