中考物理冲刺复习-电学总复习-专题2-电功和电功率训练VIP专享VIP免费

ideological and theoretical qualities and practical working ability, and strive to build a contingent of league cadres with positive work style and high quality. Hold a regular meting of the party secretary every fortnightly, arrange the work of the regiment, fedback the student information. Focus on training junior high school, junior high school secretary of the regiment branch to enable them to raise A firm political conviction, diligent and diligent learning spirit and practical and innovative work style.2:电功和电功率一、电功和电能电功： 电能： 测量电能的工具： 公式:W= = = = P= = = = 例题 1如图所示，手压电筒都有一接柄，通过塑料齿轮带动铜丝线圈内磁性飞轮高速旋转，实现切割磁感线，产生感应电流。因此它是利用 原理．把 能转化为电能。 例题 2：某月月初时，小明家的电能表的示数为 7846.6kWh，月末的示数如右图所示，若 1 度电的电费按 0.5 元计算，小明家这个月的电费是 元。 例题 3：小明用如下图所示的实验电路讨论影响电流做功多少的因素有哪些。在实验中他选取了量程合适的电流表以及三个不同规格的小电动机，在电动机的转动轴处通过细线挂着 3 个完全相同的重物，当有电流通过电动机时，转动轴开始旋转，通过绕线的方式使重物匀速上升。实验开始前他使 3 个重物分别在 A、B、C 处，高度相同。开关闭合一段时间后，重物的位置分别位于 D、E、F 处，如图所示。由此可知，电流通过电动机_____(填数字)做的功最多。实验数据记录如表，通过表中的数据可以得出结论:_______一定，_________越大，电流做功越多.Strengthen the team connection, strengthen the knowledge education among the students (especially the first grade students), and promote the formation of good school spirit with the influence of the league members. All League branches should start with recommending outstanding students as the development objects of the League, take amateur league schools as the basis, conscientiously do a good job in the work of pre-league education, league members...