1) Cho mach dien nhu hinh 2.6: UAB = 18V, I2 = 2A
a) Tim R2: R1 = 5Ω, R3 = 3Ω
1) Cho mach dien nhu hinh 2.7:
R1 = R2 = 4Ω; R3 = 6Ω; R4 = 12Ω; R5 = 0,6Ω; UAB = 12V; RA ≈ 0
a) Tinh RAB
b) Tim I qua cac dien tro, va so chi cua Ampe ke
1) Cho mach dien nhu hinh 2.5
Cho biet UAB = 20V, R1 = 2Ω; R2 = 1Ω; R3 = 6Ω; R4 = 4Ω
a) Tinh cuong do dong dien qua cac dien tro khi K mo
b) Tinh cuong do dong dien qua cac dien tro khi K dong va I qua K
1) Cho mach dien nhu hinh ve:
Moi nguon co e = 6V, r = 1Ω, R1 = 2Ω, R2 = R3 = 6Ω . Tinh:
a) eb, rb
b) U, I qua moi R
1) Cho mach dien nhu hinh 2.8:
Cho biet UAB = 30V, cac dien tro giong nhau va co tri 6Ω. Tinh I mach chinh va I6
cho mach dien nhu hinh ve
UAB=18 V. Cac dien tro R1 =12 om ,R2=8 om . Dien tro cua ampe ke khong dang ke
a, khoa K mo ,ampe ke chi bao nhieu?Tinh hieu dien the hai dau moi dien tro R1 va R2
b,khoa K dong ,ampe ke chi 0,5 A .Tinh cuong do dong dien qua R2 va tinh dien tro R3
Cho mach dien co so do nhu hinh ve trong do cac dien tro R1 = 14Ω , R2 = 14Ω , R3 = 24Ω dong dien di qua R1 co cuong do la I1 = 0,4A
a) Tinh cac cuong do dong dien I2 , I3 tuong ung di qua cac dien tro R2 , R3
b) Tinh cac hieu dien the UAC ; UCB va UAB
a) \(R_1nt(R_2//R_3)\)
\(R_1=\dfrac{U_1}{I_1}\Rightarrow U_1=0,4.14=5,6\left(V\right)\)
\(I_1=I_{AB}=0,4A\)
Có \(R_{AB}=R_1+R_{23}=14+\dfrac{R_2.R_3}{R_2+R_3}=\dfrac{434}{19}\left(\Omega\right)\)
\(\Rightarrow U_1+U_{23}=U_{AB}=R_{AB}.I_{AB}=\dfrac{439}{19}.0,4=\dfrac{868}{95}\left(V\right)\)
\(\Rightarrow U_{23}=\dfrac{868}{95}-5,6=\dfrac{336}{95}\left(V\right)\)
\(\Rightarrow U_2=U_3=\dfrac{336}{95}\left(V\right)\)
\(I_2=\dfrac{U_2}{R_2}=\dfrac{24}{95}\left(A\right)\)
\(I_3=\dfrac{U_3}{R_3}=\dfrac{14}{95}\left(V\right)\)
b) \(U_{AB}=\dfrac{868}{95}\left(V\right)\)
\(U_{AC}=I_1.R_1=0,4.14=5,6\left(V\right)\)
\(U_{CB}=I_{23}.R_{23}=0,4.\dfrac{R_2.R_3}{R_2+R_3}=\dfrac{336}{95}\left(V\right)\)
Vậy...
cho mach dien nhu hinh ve hdt hai dau doan mach U= 84V Biet R1 = 2 R2 va R3 = 10om so chi cua ampe ke A la 6 ampe . Tinh dong dien qua cac dien tro R1 r2 va gia tri R1 R2
mắc nối tiếp hay song song vậy bạn
Cho mach dien R1 noi tiep (R2song song R3) biet R1= 6, UAB=6V ,R3=4,I2=0,66A tinh R2
Vì R1nt(R2//R3)\(\Rightarrow\) I1=I23 \(\Leftrightarrow\) I1=0,66+I3
Ta có :UAB=U1+U3=6.(0,66+I3) +4.I3=3,96+6.I3+4.I3=3.96+10.I3
\(\Rightarrow\)6=3.96+10.I3\(\Leftrightarrow\)I3=0,204A
+ I23=I2+I3=0,66+0,204=0,864A
+Vì R1ntR23 nên :I1=I23=I tổng =0,864A
U1=I1.R1=0,864.6=5,184V
U23=Uab-U1=6-5,184=0,816V
+Vì R2//R3 nên : U2=U3=U23=0,816V
R2=U2/I2=0,816/0,66=1,2
