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What is the dimensional formula for the universal gravitational constant G? (Hint: use F = G*m1*m2 / r²)

1. M¹L³T⁻²
2. M⁰L²T⁻²
3. M⁻¹L²T⁻²
4. M⁻¹L³T⁻²

Correct answer: M⁻¹L³T⁻²

Solution

Rearranging F = Gm1m2/r² gives G = Fr²/(m1m2). Substituting dimensions: [G] = (MLT⁻²)(L²)/M² = M⁻¹L³T⁻².

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