Question

Các cao nhân ơi xin hãy giúp em😿😿

Answer 1

hơi nhiều nên làm vài bài thoi còn lại bạn tự làm

16. R1 //(R2 nt R3)

\(=>U123=U1=U23=Im.Rtd=2.\left\{\dfrac{R1\left(R2+R3\right)}{R1+R2+R3}\right\}=15\left(V\right)\)

\(=>I1=\dfrac{U1}{R1}=\dfrac{15}{12}=1,25A\)

\(=>I23=I2=I3=\dfrac{U23}{R2+R3}=\dfrac{15}{15+5}=0,75A\)

17. R1 nt(R2 //R3)

a,\(=>Rtd=R1+\dfrac{R2R3}{R2+R3}=4+\dfrac{6.12}{6+12}=8\left(om\right)\)

b,\(=>I1=I23=\dfrac{U}{Rtd}=\dfrac{24}{8}=3A=>U23=U2=U3=I23.R23=3.4=12V=>I2=\dfrac{U2}{R2}=2A,I3=\dfrac{U3}{R3}=1A\)

19. R3 nt(R1//R2)ntRa

\(=>U12=\dfrac{R1R2}{R1+R2}=\dfrac{24R2}{24+R2}=U-Ua-U3=24-1.0,2-1.3,8=>R2=120\left(om\right)\)

20. R3 nt Ra nt(R1//R2)(làm tương tự)

18. (R1 nt R2)//R3

\(a,=>Rtd=\dfrac{R3\left(R1+R2\right)}{R3+R1+R2}=4\left(om\right)\)

\(b,=>U3=U12=12V=>I3=\dfrac{U3}{R3}=1A,=>I1=I2=\dfrac{U12}{R1+R2}=\dfrac{12}{2+4}=2A\)

c,\(=>U1=I1R1=4V=>U2=I2R2=8V\)

(mấy bài còn lại lm tương tự)