{
  "correct_letter": "B",
  "correct_formula": "ΣM_ext = 0",
  "annotation": "Environment: g=9.81, F_drag=!=0",
  "choices": [
    "v = f·λ",
    "ΣM_ext = 0",
    "ΣF_ext = m·g·tan(α_eq)",
    "G = m·g"
  ],
  "correct_index": 1,
  "physics_type": "AtRest",
  "seed": "AtRest|NewtonsFirstLaw/AtRest/2",
  "is_realworld": true,
  "dropped_wrong_formulas": [
    "F_drag = (1/2)·C_d·ρ·A·v²"
  ]
}