9.\(=>\dfrac{1}{Rtd}=\dfrac{1}{R1}+\dfrac{1}{R2}+\dfrac{1}{R3}=\dfrac{1}{R}+\dfrac{1}{R}+\dfrac{1}{R}=>\dfrac{1}{Rtd}=\dfrac{3}{R}=>Rtd=\dfrac{R}{3}\)
10.\(=>Im=I1+I2=0,5+0,7=1,2A\)
11.\(=>I1=I-I2=1,2-0,5=0,7A\)
12.\(Rtd=\dfrac{R1R2}{R1+R2}=\dfrac{3.6}{3+6}=2\left(om\right)\)
13\(U=220V\)
15.\(Rtd=\dfrac{R1R2}{R1+R2}=>3=\dfrac{6R2}{6+R2}=>R2=...\)
14.\(Rtd=\dfrac{R^2}{2R}=\dfrac{R}{2}=>R=2Rtd=>Rtd=\dfrac{R}{2}\)
16.\(=>\dfrac{1}{Rtd}=\dfrac{1}{R1}+\dfrac{1}{R2}+\dfrac{1}{R3}=>Rtd=1\left(om\right)=>Im=UI=6A\)
17.\(=>Im=\dfrac{I2R2}{\dfrac{R1R2}{R1+R2}}=\dfrac{2.10}{\dfrac{5.10}{5+10}}=6A\)
18.\(=>Im=\dfrac{3,2}{\dfrac{R1R2}{R1+R2}}=2A\)
19.\(=>\dfrac{1}{Rtd}=\dfrac{1}{25}+\dfrac{1}{50}+\dfrac{1}{50}=>Rtd=.....\)
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