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Question
Draw the effective equivalent circuit of the circuit shown in figure, at very high frequencies and find the effective impedance.
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Solution
The element with infinite resistance will be considered as open circuit and the element with zero resistance will be considered as short-circuited.
In similar way, `X_C = 1/(2pivC)`
At high frequency, XC will be low.
So reactance of capacitance can be considered negligible and capacitor can be considered as short-circuited.
Here the above figure is equivalent circuit to given circuit.
Total impedance,Z = R1 + R3
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