| { | |
| "correct_letter": "B", | |
| "correct_formula": "ΣM_ext = 0", | |
| "annotation": "Environment: g=9.81, F_drag=!=0", | |
| "choices": [ | |
| "W = ΔE_k = (1/2)·m·v_t² - (1/2)·m·v_0²", | |
| "ΣM_ext = 0", | |
| "ΣF = m·Δv / (Δt·cosθ)", | |
| "B = μ_0·I / (2π·r)" | |
| ], | |
| "correct_index": 1, | |
| "physics_type": "AtRest", | |
| "seed": "AtRest|NewtonsFirstLaw/AtRest/9", | |
| "is_realworld": true, | |
| "dropped_wrong_formulas": [ | |
| "F_drag = (1/2)·C_d·ρ·A·v²" | |
| ] | |
| } | |