Question

     mn giúp e 307 vs

Answer 1

R1 //{R2  nt(R3//R4)}

\(\Rightarrow Icb=4=I1+I3=\dfrac{Uab}{R1}+I3=\dfrac{Uab}{4}+I3\left(1\right)\)

\(\Rightarrow\dfrac{R3}{R4}=2\Rightarrow R3=2R4\Rightarrow\dfrac{I3}{I4}=0,5\Rightarrow I4=\dfrac{I3}{0,5}\left(A\right)\)

\(\Rightarrow I2=I3+I4\Rightarrow I3+\dfrac{I3}{0,5}=I2\Rightarrow1,5I3=0,5I2\Rightarrow I3=\dfrac{I2}{3}=\dfrac{\dfrac{Uab}{R234}}{3}=\dfrac{\dfrac{Uab}{12}}{3}=\dfrac{Uab}{36}\left(A\right)\left(2\right)\)

\(\left(1\right)\left(2\right)\Rightarrow4=\dfrac{Uab}{4}+\dfrac{Uab}{36}\Rightarrow Uab=14,4V\)