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Question
What do you mean by a gravitational constant?
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Solution
- From Newton’s law of gravitation,
F = G`("m"_1"m"_2)/"r"^2`
where, G = constant called universal gravitational constant. Its value is 6.67 × 10-11 N m2/kg2. - G = `"Fr"^2/("m"_1"m"_2)`
If m1 = m2 = 1 kg, r = 1 m then F = G.
Hence, the universal gravitational constant is the force of gravitation between two particles of unit mass separated by unit distance.
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