Question

Cho R1 =R2=10Ω

        R3= 30Ω

        UAB =24V

a) tính Rtđ

b)Tính số chỉ trên ampe kế

c) Tính U1 , U2 , U3

Answer 1

\(R_{12}=R_1+R_2=10+10=20\left(\Omega\right)\)

\(R_{tđ}=\dfrac{R_{12}.R_3}{R_{12}+R_3}=\dfrac{20.30}{20+30}=12\left(\Omega\right)\)

\(A=\dfrac{U_{AB}}{R_{tđ}}=\dfrac{24}{12}=2\left(A\right)\)

\(U=U_{12}=U_3=24V\)

\(I_{12}=I_1=I_2=\dfrac{U_{12}}{R_{12}}=\dfrac{24}{20}=1,2\left(A\right)\)

\(\left\{{}\begin{matrix}U_1=I_1.R_1=1,2.10=12\left(V\right)\\U_2=I_2.R_2=1,2.10=12\left(V\right)\end{matrix}\right.\)