由广东教育出版社2007年最新发行的普通高中课程标准实验教科书、物理课本(必修2)第9页练习题第4题.对该题题目及教师参考书的答案,本人认为值得商榷.这道题是这样的:如图1所示,MN是流速恒定的河流,小船自A点渡河,第1次小船沿AB航行,到达对岸所用时图1间为tA,第2次沿AC航行,到 The answer to this question and the teacher’s reference book by the Guangdong Normal Education Publishing House in 2007, the most recent release of the general high school curriculum standard experiment textbooks, physics textbooks (required 2), page 9, practice question 4, I think it is worth discussing. The question is this: As shown in Figure 1, MN is a river with a constant flow rate. The boat crosses the river from point A. The first boat sails along AB. When it reaches the opposite bank, it is used as tA between the first and second time along the AC.