- , ... R C.
I = I∙sinωt,
, .
, , - : U = Uc + (*)
:
= ∙sinωt, π / 2:
Uc = Uc∙sin(ωt - π/2)
I, Uc , , U.
, I U, π/2, , φ. 0 π/2 : R φ .
U :
U = = I = I∙Z,
Z = .
:
tgφ = Uc/ = (1/ωC)/R = 1/(ω∙R∙C)
16. . . , , , .
.4.24. .
, , , .
U = UL + Uc + UR
, , π⁄2, π⁄2. :
UR = UmR∙sinωt = Im∙R∙sinωt
UL = UmL∙sin(ωt + π/2) = Im∙ω∙L∙sin(ωt + π/2)
Uc = Umc∙sin(ωt - π/2) = (Im/ωC)∙sin(ωt - π/2)
U.
.4.25. .
φ :
U = = IZ,
Z = , .
tgφ = (UL - Uc)/UR = .
UL, Uc UR. UL - Uc > 0 φ . UL Uc . . .4.26, UL = Uc .
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. 4.26. :
- ; - .
, (. 4.27), R - , Z - , X = XL - Xc - .
.4.27. .
, R = Z∙cosφ; X = Z∙sinφ.
, 180 , , (.4.26, ).
, , , . .
:
UL = Uc, XL = Xc ω = 1/ ω∙,
ω - . :
I = U / = U/R
, φ = 0, cosφ = 1. . . XL .
U / UL = I∙Z / I∙XL = Z / XL U∙L = U∙(XL / R), .. XL/R . , .
(4.31).
ω∙L = 1 / (ω∙);
ω²∙L∙ = 1;
ω = = , ω = 2πf, 2πf = ,
f = ,
f - ;
L - ;
- .