Of course.
Wheat had no idea what Xu Yun was thinking. At this moment, he was holding a fountain pen, quickly sketching out a force analysis on the paper:
"Mr. Luo Feng says to ignore gravity, so we only need to analyze the tension T at both ends of segment AB."
"Segment AB experiences a left-downward tension T at point A and a right-upward tension T at point B, both equal in magnitude."
"But this segment is curved, so the directions of the two T's are not the same."
"Suppose the angle between the tension at point A and the horizontal axis is θ, then it's obvious that the angle at point B is different—let's call it θ+Δθ."
"Because the points on the segment move up and down during oscillation, we only need to consider the vertical component of tension T."
"At point B, the upward tension is T·sin(θ+Δθ); at point A, the downward tension is T·sinθ. So, the net force in the vertical direction for the whole AB segment is the difference between these two forces..."
Soon enough,
