Question

Giúp mk với

Answer 1

Chọn C.

\(I_m=\dfrac{\xi_1+\xi_2}{r_1+r_2+R_1}=\dfrac{2,4+3}{0,1+0,2+3,5}=\dfrac{27}{19}A\)

\(\Rightarrow I_{DF}=I_m=\dfrac{27}{19}A\)

\(\Rightarrow U_m=U_{DF}=I_m\cdot R_1=\dfrac{189}{38}V\)

\(\Rightarrow U_{23}=\dfrac{189}{38}V\)

\(\Rightarrow I_3=I_{23}=\dfrac{U_{23}}{R_{23}}=\dfrac{189}{38}:8=\dfrac{189}{304}A\) 

\(\Rightarrow\) \(U_{AF}=U_3=\dfrac{189}{304}\cdot4=2,48V\)