Solving voltage divider involving capacitors

AI Thread Summary
The discussion revolves around solving a voltage divider problem involving capacitors and resistors, with given values for impedances and a target ratio of VV/VC. The user attempts to calculate the equivalent impedance ZV using the formula for parallel resistances and finds ZV to be 50Ω. However, upon calculating the voltage ratio VV/VC, the result is approximately 0.02499, which is significantly lower than the expected value of 0.04789. The user seeks clarification on potential errors in their calculations and confirms that the voltage across ZV1, ZV2, and CV is indeed the same. The conversation highlights the need for careful arithmetic and application of circuit laws.
wu_weidong
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Homework Statement


2cymnon.png

Given ZV1 = ZV2 = 100Ω,
ZCCV = ZCV = 2000/j = -2000j, and
VV/VC = 0.04789.

I'm trying to get the given VV/VC result.

Homework Equations


I know that
1/ZV = 1/ZV1 + 1/ZV2 + 1/ZCV
VV = ZV / (ZV + ZCCV) * VC

The Attempt at a Solution


1/ZV = 1/ZV1 + 1/ZV2 + 1/ZCV = 1/100 + 1/100 + j/2000
|1/ZV| = √(0.022 + (1/2000)2) = 0.02
ZV = 50Ω

VV/VC = ZV / (ZV + ZCCV) = 50 / (50 - 2000j)
VC/VV = (50 - 2000j) / 50 = 1 - 40j
|VC/VV| = √(12 + 402) = 40.01
VV/VC = 1/40.01 = 0.02499
which is about half of the value I should get.

Where did I go wrong?
 
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Kirkoffs laws - check arithmetic.
 
Simon Bridge said:
Kirkoffs laws - check arithmetic.
Can I please have a bit more hint?

The voltage through ZV1, ZV2 and CV is the same (VV), right?
 
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