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2016年河北省中考物理实行网上电子阅卷,每份试卷至少阅两遍,笔者参与了37题的阅卷工作,在阅卷过程中发现了不少问题,愿与各位同仁共同分析,以期改进我们今后的教学,提高物理课堂教学效率,最大限度提高学生物理学习的成绩.第37题如图1所示,某建筑工地用电动机、定滑轮和斜面组成的装置,将重为1600 N的建材由斜面底端匀速拉到顶端.已知斜面倾角为30°,斜面高为4.5 m,建材移动的速度为0.4 m/s,电动机的输出功
In 2016, in Hebei Province, senior high school entrance examination physics online electronic marking, each paper at least read twice, I participated in the 37 questions marking work, in the marking process found a lot of problems, is willing to work with colleagues to analyze together, with a view to improving our future Teaching, to improve the efficiency of physical classroom teaching, to maximize the students’ physical learning achievements.As shown in Figure 1, a construction site with a motor, fixed pulley and bevel device composed of a weight of 1600 N building materials from the bevel Uniform speed to the top.It is known that the incline angle is 30 °, the incline height is 4.5 m, the moving speed of the building material is 0.4 m / s, the output power of the motor