[쿼크에서 빅뱅까지 (2021)] 2.2 운동량과 에너지

New channel 물리학 산책: title sample judged 'whole' (Full-length structured physics and big-history lecture series with consistent, genuine course content and colloquium tal); passed a second screen for sellers/exam-prep/re-uploads; 3 of 3 sampled transcripts showed teaching, 0 not; every title checked strictly; oEmbed verified.