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在输送一定功率的电能时,为减少输电导线因发热而损失的电能,有效的方法是 (填“提高”成“降低”)送电的电压:若变压器副线圈两端的电压大于原线圈两端的电压,则副线圈的匝数 (填“大于”“小于“...
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高三上学期物理《》真题及答案
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在输送一定功率的电能时为减少输电导线因发热而损失的电能有效的方法是填提高成降低送电的电压若变压器副
某发电站采用__输电向外输送电能若输送的总功率为P0输电电压为U.输电导线的总电阻为R.则下列说法正
输电线上的电流
输电线上的电流
输电线上损失的功率
输电线上损失的功率
远距离输送一定功率的交流电若输送电压提高到n倍则
输电线上的电压损失减少到原来的(n-1)/n倍
输电线上的电能损失不变
输电线上的电能损失减少到原来的(n
2
-1)/n
2
输电线上的电压损失减少到原来的1/n
远距离输电时送电功率一定为了减少输电线上电能损失应
减小输送电压,增大输送电流
减小输送电压,减小输送电流
提高输送电压,减小输送电流
提高输送电压,增大输送电流
关于远距离输电下面说法正确的是
在输电功率一定的条件下,根据P=U2/R可知,导线发热损失功率与输电电压平方在正比,与输电线电阻在反比
在输电功率一定的条件下,根据P=I2R可知,导线发热损失功率与输电电流平方成正比,与输电线电阻成正比
在输电功率一定的条件下,输电线损失功率与输电电压平方成反比
在输电功率和电压一定的条件下,输电线损失功率与输电线的直径平方成正比
西电东送是将我国西部发电车发出的电输送到我国东部由发电厂输出的电功率是一定的它决定于发电机组的发电能
对于电能输送的以下说法中正确的是
输送电能的基本要求是:可靠、保质、经济
减小输电导线上功率损失的唯一方法是采用__输电
减小输电导线上功率损失的唯一方法是增大导线的横截面积
实际输送电能时,要综合考虑各种因素,如:输送功率大小、距离远近、技术和经济条件等
为了将发电厂的电能输送到远处的用户家中在两地间架设了两根等长的输电线.两根输电线的总电阻为r.已知
某发电站采用__输电向外输送电能若输送的总功率为P0输电电压为U.输电导线的总电阻为R.则下列说法正
输电线上的电流为
输电线上的电流为
输电线上损失的功率为
输电线上损失的功率为
在远距离输电中为了减小电流通过输电线造成的发热损失在输电功率一定的情况下一种有效的措施是减小输电电
在远距离输电中为了减小电流通过输电线造成的发热损失在输电功率一定的情况下一种有效的措施是减小输电电流
图为远距离__输电的示意图关于远距离输电下列表述正确的是
增加输电导线的横截面积有利于减少输电过程中的电能损失
__输电是通过减小输电电流来减小电路的发热损耗
在输送电压一定时,输送的电功率越大,输电过程中的电能损失越小
__输电必须综合考虑各种因素,不一定是电压越高越好
如图所示为远距离__输电示意图关于远距离输电下列表述错误的是
增加输电导线的横街面积有利于减少输电过程中的电能损失
__输电是通过减小输电电流来减少电路的发热损耗的
在输送电压一定时,输送的电功率越大,输电过程中的电能损失越小
__输电必须综合考虑各种因素,不一定是电压越高越好
发电站通过升压变压器输电导线和降压变压器把电能输送到用户升压变压器和降压变压器都可视为理想变压器若发
输送一定功率的电能时为了减少电线上的电能损失可采取输电的办法.
图为远距离__输电的示意图关于远距离输电下列表述正确的是
减少输电导线的横截面积有利于减少输电过程中的电能损失
__输电是通过增大输电电流来减少电路的发热损耗
在输送电压一定时,输送的电功率越大,输电过程中的电能损失越大
__输电一定是电压越高越好
在远距离输电中为了减小电流通过输电线造成的发热损失在输电功率一定的情况下一种有效的措施是减小输电电流
下列说法正确的是
__输电的目的是加快电流输送速度
增大输电线的电阻可以减少输电线的电能损失
输送一定功率电能,电压越高,电能损失越少
以上说法均不对
西电东送是将我国西部发电车发出的电输送到我国东部由发电厂输出的电功率是一定的它决定于发电机组的发电能
在远距离输电中为了减小电流通过输电线造成的发热损失在输电功率一定的情况下一种有效的措施是减小输电电流
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