想問 B part 個 theta 都冇比到底係點做? 救命呢課就快攪到我痴線 所以真係好憎physics take moment about point A or B dse physics 有教coefficient of friction咩?
想問 B part 個 theta 都冇比到底係點做? 救命呢課就快攪到我痴線 所以真係好憎physics