両手で水平に紙を持って片手で手放すと、紙が下に傾いています。これは、紙の重心と手が手を保持している側に向かってシフトし、不均衡な力が紙を下に引っ張らせるために起こります。介入せず、片手で紙を持っていない場合、紙はもう一方の手からぶら下がっている新しいバランスを見つけるでしょう。
If you hold a piece of paper horizontally with two hands and let go of one hand, the paper will tilt downwards on the side of the hand you released. This happens because the center of gravity of the paper and your hands is shifted towards the side that still has your hand holding it, causing the unbalanced force to pull the paper downwards. If you don't intervene and still hold the paper on one hand, the paper will find a new balance hanging from your other hand.