Question

Giúp mình với

Answer 1

a. Ta có: \(I_x=\dfrac{U_{AB}}{R_x+R_3}=\dfrac{48}{18+12}=1,6\left(A\right)\)

\(\Rightarrow U_3=I_xR_3=1,6.12=19,2\left(V\right)\)

b. Ta có: \(I_1=2I_x\Leftrightarrow\dfrac{U_{AB}}{R_1+R_2}=2\dfrac{U_{AB}}{R_x+R_3}\Leftrightarrow\dfrac{1}{5+15}=\dfrac{2}{R_x+12}\)

\(\Rightarrow R_x=28\left(\Omega\right)\)