Question

E cần gấp ạ

Answer 1

Bài 1.

CTM: \(\left(R_1//R_2\right)ntR_3\)

a)\(R_{12}=\dfrac{R_1\cdot R_2}{R_1+R_2}=\dfrac{10\cdot20}{10+20}=\dfrac{20}{3}\Omega\)

\(R_{tđ}=R_{12}+R_3=\dfrac{20}{3}+5=\dfrac{35}{3}\Omega\)

b)\(I_3=I=\dfrac{U}{R}=\dfrac{15}{\dfrac{35}{3}}=\dfrac{9}{7}A\)

\(U_1=U_2=U_{12}=\dfrac{9}{7}\cdot\dfrac{20}{3}=\dfrac{60}{7}V\)

\(I_1=\dfrac{U_1}{R_1}=\dfrac{\dfrac{60}{7}}{10}=\dfrac{6}{7}A\)

\(I_2=\dfrac{U_2}{R_2}=\dfrac{\dfrac{60}{7}}{20}=\dfrac{3}{7}A\)