In physics, the capital letter 'G' stands for the Universal Gravitational Constant. This is a massive, unchanging number that dictates the strength of gravity across the entire universe, pulling planets and stars together.
The dimensional formula of the Universal Gravitational Constant (G) is [Mā»Ā¹ L³ Tā»Ā²].
Quantity: Universal Gravitational Constant (Capital 'G').
Formula Used: Newton's Law of Gravitation [F = G(m1m2)/r²].
Dimensional Formula: [Mā»Ā¹ L³ Tā»Ā²].
SI Unit: N·m²/kg².
Universal Value: The value of G is exactly 6.674 Ć 10ā»Ā¹Ā¹ NĀ·m²/kg² everywhere in the universe.
We cannot guess the dimension of G. We must derive it mathematically using Newton's Universal Law of Gravitation. The formula states the force (F) between two masses (m1 and m2) separated by a distance (r) is:
F = G (m1 à m2) / r²
Step 1: Rearrange the formula to isolate 'G' on one side: G = (F à r²) / (m1 à m2)
Step 2: Substitute the known dimensions of Force, Distance, and Mass into the equation.
Step 3: Put them into the rearranged formula: G = ( [M¹ L¹ Tā»Ā²] Ć [L²] ) / [M²]
Step 4: Simplify the equation using basic algebra (laws of exponents):
Final Dimension of G = [Mā»Ā¹ L³ Tā»Ā²].
Using the formula G = (F à r²) / (m1 à m2), we can also find the SI unit without memorizing it:
The dimensional formula for capital G is [Mā»Ā¹ L³ Tā»Ā²].
You rearrange Newton's Law of Gravitation to G = (F Ć r²) / (m1 Ć m2). Then, you plug in the dimensions for force [MLTā»Ā²], distance [L²], and mass [M²] and simplify.
No. Capital G is a universal constant with dimension [Mā»Ā¹ L³ Tā»Ā²]. Small g is acceleration due to gravity with dimension [Mā° L¹ Tā»Ā²].
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