試題詳解

36. A uniform beam of weight 300 N and length 3.0 m is suspended horizontally. On the left it is hinged to a wall; on the right it is supported by a cable bolted to the wall at distance D above the beam. The tension on the cable is 250 N. What value of D corresponds to that tension?
(A) 1.25 m
(B) 1.50 m
(C) 1.75 m
(D) 2.00 m
(E) 2.25 m