Question

Answer 1

a,theo bài ra \(=>R1//R2\)

ampe kế A chỉ 5A=>Im=I12=5A

ampe kế A2 chỉ 2A=>I2=2A

\(=>Rtd=\dfrac{Uab}{5}\left(om\right)\)

\(=>Rtd=\dfrac{Uab}{I12}=\dfrac{Uab}{I1+I2}=\dfrac{Uab}{\dfrac{Uab}{45}+\dfrac{Uab}{\dfrac{Uab}{2}}}\left(om\right)\)

\(=>\dfrac{Uab}{5}=\dfrac{Uab}{\dfrac{Uab}{45}+2}=>Uab=135V\)

b, giữ nguyên Uab=135V

\(=>R3//R2\)

ampe kế A chỉ 6A\(=>Im=I23=6A\)

\(=>Rtd=\dfrac{Uab}{Im}=\dfrac{135}{6}=22,5\left(om\right)\)\(=R23\)\(=\dfrac{67,5+R3}{67,5.R3}=>R3=33,75\left(om\right)\)

\(=>Ia2=2A\)