Its value is independent of the nature of the intervening medium, location, and time.
Explanation
According to Newton's Law of Universal Gravitation, the force of attraction between two bodies is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. This relationship is expressed as:
F = G (m₁m₂) / r²
Here, G represents the Universal Gravitation Constant.
Detailed Analysis:
- The constant G is termed "universal" because its value remains constant everywhere in the universe.
- Independence from Medium: Unlike electric or magnetic forces, the gravitational force (and consequently the value of G) is not affected by the nature of the medium separating the two masses.
- Independence from Physical Conditions: The value of G does not depend on factors such as temperature, pressure, or the chemical composition of the bodies involved.
- Independence from Location and Time: The value applies equally to terrestrial objects and celestial bodies, and it does not change with time or location in space.
Incorrect Options Analysis:
- It is applicable only to heavenly bodies in the universe. is incorrect: The law applies to all material objects having mass, not just heavenly bodies.
- It varies with the expansion of the universe. is incorrect: G is a fundamental physical constant and does not vary with the expansion of the universe.
- It is derived from the universal gas constant. is incorrect: The Universal Gas Constant (R) is a thermodynamic constant and is unrelated to the derivation of G.
Key Takeaway:
The Universal Gravitation Constant (G) is a scalar constant whose value ($6.67 \times 10^{-11} \, \text{Nm}^2/\text{kg}^2$) is independent of the nature of the masses, the intervening medium, location, and time.