“…They investigated conceptual physics understanding on mechanics [107,227,231,232], electricity [224,228,230], magnetism [226], fluid [104,229], work and energy [225,233,234], thermodynamics [106], and modern physics [235]. Within the context of the Indonesian PER literature, we propagate conceptual understanding in another form of multiple representations [225,236,237], including external representation [105], mental model [238], drawing ability on free-body diagram [239,240], and mathematical representation [232].…”