{
  "correct_letter": "B",
  "correct_formula": "y = h + x·tanθ - g·x² / (2·v_0²·cos²θ)",
  "annotation": "Environment: g=9.81, F_drag=!=0\nGround: e=0.5\nSteelBall: d = 0.04, e = 0.6, h = 0.75, v_0 = 0.56",
  "choices": [
    "y = h·cos(g·x / v_0²) + x·tanθ",
    "y = h + x·tanθ - g·x² / (2·v_0²·cos²θ)",
    "m·g·h + (1/2)·m·v_0² = constant",
    "F = G·m_1·m_2 / r²"
  ],
  "correct_index": 1,
  "physics_type": "Projectile",
  "seed": "Projectile|Gravity/Projectile/6",
  "is_realworld": true,
  "dropped_wrong_formulas": [
    "F_drag = (1/2)·C_d·ρ·A·v² (A = π·(d/2)²)"
  ]
}