《物理教学探讨》2005年第二期(上半月刊)载了王振环老师的文章《关于两道习题的讨论》。在该文例题二中作者分别用了二种解法得到两个不同结果。笔者认为解法一欠妥。纵观《万有引力定律》一章,该章公式虽然较多,但我们做题的思路却是很明确的,主要有两点:(1)当题目涉及环绕天 The “Physics Teaching Research” second issue (first half month) in 2005 contained Wang Zhenhuan’s article “Discussion on Two Exercises”. In this second example, the author used two solutions to obtain two different results. The author believes that the solution is not right. Looking at the chapter “The Law of Universal Gravity”, though there are many formulas in this chapter, the thinking of our questions is very clear. There are two main points: (1) When the topic involves round-the-day