hello I have a problem in calculating the equivalent impedance of a simple AC circuit, where the impedances are:(adsbygoogle = window.adsbygoogle || []).push({});

Z1 = 5+i20

Z2 = 5+i20

Z3 = 10-i2,5

Z4 = -i10

Z5 = 5

and I need to find:

Z_eq = Z3 // [(Z1 // Z4) + (Z2 // Z5)]

where the + indicates 2 components in serie and the // indicates 2 components in parallel.

My calculations always bring me to

Z_eq=6,25-i3,75

but my book says Z_eq=28,33.

Which is the correct eqv impedance?

Thank you

PS-I used the formula Za//Zb = (Za*Zb)/(Za+Zb)

to calculate equivalent impedances of two components in parallel, and the sum for components in serie.

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# Homework Help: Equivalent impedance

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