Question

Cho mạch điện:

R₁ = 10 Ôm

R₂ = 3 R₃

I₁ = 4 A

_______________________________

I₂ = ?

I₃ = ?

U₃ = 15 V . U_AB = ?

Answer 1

R1ntR23 => I1=I23=4(A)

R2//R3

\(\Rightarrow\dfrac{I_2}{I_3}=\dfrac{R_3}{R_2}\)

\(\Leftrightarrow\dfrac{I_2}{R_3}=\dfrac{I_3}{3R_3}=\dfrac{4}{4R_3}=\dfrac{1}{R_3}\)

\(\Rightarrow\left\{{}\begin{matrix}I_2=1\left(A\right)\\I_3=3\left(A\right)\end{matrix}\right.\)

R2//R3 => U3=U2=15(V)

U1=R1.I1=10.4=40(V)

U_AB=U1+U23=40+15=55(V)