两个定值电阻并联后的总电阻怎么算 两个定值电阻，把它们串联起来，等效电阻是4Ω；把它们并联起来...
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\uff081\uff09\u8bbe\u6bcf\u4e2a\u7535\u963b\u7684\u963b\u503c\u4e3aR\uff0e\u5219\u4e32\u8054\u540e\u4e3aR2=2R=4\u03a9\uff0c\u5e76\u8054\u540e\u7535\u963b\u4e3aR1=12R=1\u03a9 \u6240\u4ee5\u4e24\u4e2a\u7535\u963b\u7684\u963b\u503c\u5404\u662fR=2\u6b27\uff0e\uff082\uff09\u5982\u679c\u628a\u8fd9\u4e24\u4e2a\u7535\u963b\u4e32\u8054\u540e\u63a5\u5165\u4e00\u4e2a\u7535\u52a8\u52bf\u4e3a?\uff0c\u5185\u963b\u4e3ar\u7684\u7535\u6e90\u4e24\u6781\u95f4\uff0c\u6b64\u65f6\u7535\u6d41I1=?r+4\uff0c\u4e24\u7535\u963b\u6d88\u8017\u7684\u603b\u529f\u7387\u7b49\u4e8eP1=I21R2=4I21\uff1b\u5982\u679c\u628a\u8fd9\u4e24\u4e2a\u7535\u963b\u5e76\u8054\u540e\u63a5\u5165\u540c\u4e00\u7535\u6e90\u4e24\u6781\u95f4\uff0c\u6b64\u65f6\u7535\u6d41I2=?R+1\uff0c\u4e24\u7535\u963b\u6d88\u8017\u7684\u603b\u529f\u7387\u7b49\u4e8eP2=I22R1=I22\uff1b\u53c8\u56e0\u4e3aP1=9W\uff0c\u4e14P2\u2265P1\u4ee3\u5165\u53ef\u5f97?=6+1.5r\uff0c\u5176\u4e2d0\uff1cr\uff1c2\u03a9\uff0e\u7b54\uff1a\uff081\uff09\u8fd9\u4e24\u4e2a\u7535\u963b\u7684\u963b\u503c\u5404\u4e3a2\u03a9\u30012\u03a9\uff1b\uff082\uff09\u6ee1\u8db3\u8fd9\u4e00\u8981\u6c42\u7684?=6+1.5r\uff0cr\u7684\u6240\u6709\u503c\u4e3a0\uff1cr\uff1c2\u03a9\uff0e
两个定值电阻并联后的总电阻等于每一个分电阻倒数之和。并联后的总电阻值比其中的任何一个分电阻的阻值都小。
公式如下：
R总=1/R1+1/R2=R1R2/R1+R2
电路图如下：
拓展：
串联电路中，总电阻等于每一个分电阻之和。总电阻比任何一个分电阻的阻值大。
R总=R1+R2。
貌似公式写错了，总电阻的倒数
两个定值电阻并联的总电阻计算公式为
R总=（R1×R2)÷(R1+R2)
即R总=（R1×R2)/(R1+R2)
并联时 1/R=1/R1+1/R2
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绛旓細R=(R1*R2)/(R1+R2)=7.25娆
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