求恒力的功用公式W=Fxcosα,求功率常用公式P=Fvcosα,但当物体做曲线运动时由于力与位移的方向的夹角或力与速度的方向夹角不断变化,直接应用公式求解繁难复杂,若把运动的分解方法运用到其中,则非常简便,快捷.一、求恒力的功例1如图1,质量为m的物体沿曲线从初位置1运动到末位置2,高度差为h,求重力做的功.解析:物体沿图示曲线的运动可分解为水平方向的运动与竖直方向的运动,重力对物体所做的功等于在水平方向运动做的功与竖直方向做功的代数和.由于重力在水平方向不做功所 Constant force utility formula W = Fxcosα, find the formula for the power P = Fvcosα, but when the object to do the curve of the movement due to force and the direction of the displacement angle or force and the angle of the direction of the angle of change, the formula directly to solve the complex Complex, if the movement of the decomposition method applied to them, it is very simple and fast. First, the constant force of the work 1 as shown in Figure 1, the mass of the object m along the curve from the initial position 1 to the last position 2, the height difference For h, for gravity to do the work. Analysis: the movement of the object along the curve can be decomposed into the horizontal direction of the movement and the vertical direction of the movement, the work of gravity on the object equal to the horizontal movement of work done with the vertical Algebraic summation of the direction of work, due to gravity in the horizontal direction do not work