{
  "correct_letter": "D",
  "correct_formula": "e = (v_2f - v_1f) / (v_1i - v_2i)",
  "annotation": "Environment: g=-9.81, F_drag=0.0\nGround: mu_s=0.0, mu_k=0.0\nWalnutCube: a = 2.0, e = 0.5, m = 5120.0, v_0 = 2.5\nGrogFiredClayCube: a = 2.0, e = 0.2, m = 16000.0, v_0 = 0.0",
  "choices": [
    "ΔE = (1/2)·[(m_1·m_2) / (m_1 + m_2)]·(v_1i - v_2i)²",
    "ΔE = (1/2)·m_1·m_2·e²·(v_1i - v_2i)² / (m_1 + m_2)",
    "F = k·q_1·q_2 / r²",
    "e = (v_2f - v_1f) / (v_1i - v_2i)"
  ],
  "correct_index": 3,
  "physics_type": "InelasticCollision",
  "seed": "InelasticCollision|benchmark/inelastic_collision/2"
}