【摘要】 讨论了各种情况下静摩擦力的方向和大小,并通过具体的物理实例,指出静摩擦力的大小和方向都应根据具体情况视之。这些讨论可以帮助学生澄清一些错误概念,从而正确地认识静摩擦力这种力学中常见的作用力,提高教学效果。更多还原

【Abstract】 The thesis discusses the magnitude and direction of static friction in different conditions,we show that the magnitude and direction of static friction are changed in different conditions.It is helpful knowledge to help the students to understand that the friction is a conmmon force in mechenics.更多还原