試題詳解

36. A uniform and thin stick of mass (m) and length (l) is held vertically by two strings of negligible mass. fmmediately after one string is cut, what is the magnitude of linear acceleration of the middle of the stick? (The moment of inertia of the thin stick is ml²/3 for an axis through one end.)

(A) g/4
(B) g/2
(C) 3g/4
(D) g
(E) 3g/2