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Step 1: Gather data from a simplified Cavendish experiment. - Mass of small ball (m1) = 0.2 kg - Mass of large ball (m2) = 2000 kg - Distance between the centers of the small and large balls (r) = 0.5 m - Length of the torsion wire (L) = 0.1 m - Measured twist angle (θ) = 0.0005 rad - Torsion constant of the wire (k) = 1.0×10⁻⁶ N·m/rad Step 2: Calculate the torque (τ) caused by the gravitational attraction: τ = k × θ = 1.0×10⁻⁶ × 0.0005 = 5.0×10⁻¹⁰ N·m Step 3: The torque is also equal to the product of the gravitational force (F) and the lever arm (r): τ = F × r → F = τ / r = 5.0×10⁻¹⁰ / 0.5 = 1.0×10⁻⁹ N Step 4: Use Newton’s law of gravitation to solve for G: F = G × (m1 × m2) / r² → G = F × r² / (m1 × m2) Plugging in the numbers: G = 1.0×10⁻⁹ × (0.5)² / (0.2 × 2000) = 1.0×10⁻⁹ × 0.25 / 400 = 2.5×10⁻¹⁰ / 400 = 6.25×10⁻¹³ This simplified calculation gives G ≈ 6.25×10⁻¹³ N·m²/kg², which is close to the real value 6.674×10⁻¹¹. The difference shows the importance of precise measurements and careful error analysis in the real experiment.