Two masses 6 kg and 3 kg are 2 m apart. Gravitational force between them (G = 6.67 × 10⁻¹¹):
A3 × 10⁻¹¹ N
B6 × 10⁻¹¹ N
C3 × 10⁻¹⁰ N
D1.5 × 10⁻¹¹ N
Answer & Solution
Correct answer: C. 3 × 10⁻¹⁰ N
F = G m1 m2 / r² = (6.67 × 10⁻¹¹)(6)(3)/4 = (6.67 × 18 / 4) × 10⁻¹¹ ≈ 30 × 10⁻¹¹ = 3 × 10⁻¹⁰ N.
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