《高中物理思维方法集解》参考系列——微积分思想在物理解题中的应用例谈

ZHONGXUEJIAOXUECANKAO

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江苏徐州市第七中学(221011)- ,Y

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l2:本题第三问中注意到功率P与时间t成正

比,所以计算焦耳热时应采用平均功率代入计算b也可

以仿照匀变速运动用v-t图求位移,作出P-t图求解

焦耳热b本题第四问求解撤力后导体棒最终在导轨上

静止时的坐标x,由于撤力后导体棒作变速运动,所以在

求解时也须想到利用微积分的思想解决问题b

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(责任编辑易志毅)