Question

Answer 1

40.

, \(\)R1 nt (R2//R3)

\(=>I1=I23=Im=0,5A\)

\(=>U23=I23.R23=U2=U3=0,5.\dfrac{24.15}{24+15}=\dfrac{60}{13}V\)

\(=>I2=\dfrac{U2}{R2}=\dfrac{5}{26}A,=>I3=\dfrac{U3}{R3}=\dfrac{4}{13}A\)

\(=>U1=I1.R1=6V\)

 

Answer 2

41 \(R1nt[\left(R2ntR3\right)//R4]\)

\(=>Rtd=R1+\dfrac{\left(R2+R3\right).R4}{R2+R3+R4}=15+\dfrac{\left(3+7\right).10}{3+7+10}=20\left(om\right)\)

\(=>Im=I1=I234=\dfrac{U}{Rtd}=1,75A\)

\(=>U1=I1.R1=26,25V\)

\(=>U234=I234.R234=1,75.\dfrac{\left(3+7\right).10}{3+7+10}=8,75V=U4=U23\)

\(=>I4=\dfrac{U4}{R4}=\dfrac{8,75}{10}=0,875A\)

\(=>I23=\dfrac{U23}{R23}=I2=I3=\dfrac{8,75}{3+7}=0,875A\)

\(=>U2=I2.R2=2,625V,U3=I3.R3=6.125V\)

 

Answer 3

39 \(R1ntR2\)

\(=>Rtd=\dfrac{U}{Im}=\dfrac{12}{0,2}=60\left(om\right)\)

b,\(R1//R2\)

\(I1=1,5I2=>\dfrac{U}{R1}=1,5.\dfrac{U}{R2}< =>\dfrac{12}{R1}=\dfrac{18}{R2}=>R1=\dfrac{12.R2}{18}\left(om\right)\)

\(=>\dfrac{R1.R2}{R1+R2}=\dfrac{U}{I}=60=>\dfrac{\dfrac{12R2}{18}.R2}{\dfrac{12R2}{18}+R2}=60=>R2=125\left(om\right)\)

\(=>R1=\dfrac{12.125}{18}=\dfrac{250}{3}\left(om\right)\)