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Karnataka Board PUCPUC Science 2nd PUC Class 12

Draw the effective equivalent circuit of the circuit shown in figure, at very high frequencies and find the effective impedance.

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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.

Diagram
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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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Chapter 7: Alternating Current - MCQ I [Page 43]

APPEARS IN

NCERT Exemplar Physics Exemplar [English] Class 12
Chapter 7 Alternating Current
MCQ I | Q 7.15 | Page 43

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