题例要发射一颗周期为80 min的人造地球卫星,是否可能?试说明理由.(人教版高中物理教科书《曲线运动·万有引力》补充习题)该题构思精巧,是典型的联系实际的物理问题,同时也是一道典型的物理估算题.它以较强的信息性、开放性与较高的灵活度的特点较物理计算题更能考察学生应用物理基础知识解决实际问题的能力.对此题不能毫无根据地盲从地进行主观臆测,应紧紧抓住该题中卫星轨道半径约等于地球的半径这一重要信息条件,充分利用万有引力与卫星相关的物理常量,应 Is it possible to try to explain the reasons for launching a man-made earth satellite with a period of 80 minutes? (PEP Supplementary Exercise for Curriculum, Gravity and Gravity, PEP) This is a well-conceived idea that is typical of the physical Problem, but also a typical physical estimation problem.It is more informational, open and higher flexibility than the physical calculation of the question to better examine students’ ability to solve practical problems with the basics of physics. Subjective conjecture can not be done blindly without any basis and should seize the important information condition that the radius of the satellite orbit equals to the radius of the Earth and take full advantage of the universal gravity related to satellites to