{ "correct_letter": "A", "correct_formula": "y = h + x·tanθ - g·x² / (2·v_0²·cos²θ)", "annotation": "Environment: g=9.81, F_drag=!=0\nGround: e=0.5\nTennisBall: d = 0.07, e = 0.75, h = 0.57, v_0 = 1.66\nSteelBall: d = 0.04, e = 0.6, h = 0.6, v_0 = 1.59", "choices": [ "y = h + x·tanθ - g·x² / (2·v_0²·cos²θ)", "R = v_0²·sin(2θ) / (g·cos²θ)", "PV^γ = constant", "a_n = v² / ρ" ], "correct_index": 0, "physics_type": "Projectile", "seed": "Projectile|Gravity/Projectile/0", "is_realworld": true, "dropped_wrong_formulas": [ "F_drag = (1/2)·C_d·ρ·A·v² (A = π·(d/2)²)" ] }