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曾有人撰文谓圆锥摆的向心力是由绳的张力的一个分力提供的(如图1),因而,其动力学方程应为 Tsinθ=mω~2lsinθ并指出,若动力学方程记为 mgtgθ=mω~2lsinθ是不对,因为向心力与重力垂直,重力不可能提供向心力,犯了概念上的错误。这涉及到高中圆周运动教学中关于向心力由谁提供的一场争论。一些同志认为,应该坚持教材中的叙述,即作匀速圆周运动的物体,其向心力是物体所受的所有外力的合力,如图1中,向心力F是mg和T的矢量和。另一些同志认为,谁提供向心力要引导学生作具体分析,应指出诸力中哪个力或哪个力的分力真正提供
It has been written that the centripetal force of a conical pendulum is provided by a component of the tension of the rope (Fig. 1). Therefore, its dynamic equation should be Tsinθ=mω~2lsinθ and indicates that if the kinetic equation is recorded as mgtgθ=mω The ~2lsinθ is wrong, because the centripetal force is perpendicular to gravity, gravity cannot provide centripetal force, and makes a conceptual mistake. This involves a controversy over who provided the centripetal force in the high school circular movement teaching. Some comrades believe that the narrative in the textbook should be adhered to, that is, an object that is moving at a constant speed. The centripetal force is the resultant force of all external forces on the object. As shown in Figure 1, the centripetal force F is the vector sum of mg and T. Some other comrades believe that whoever provides the core force to guide students in specific analysis should point out which forces or forces in the forces actually provide