Question

A practical current source has input impedance in... a) series b) parallel c) none of these. ​

Answer 1

A particular current source has input impedance

in series always

reason:-

A current source is the dual of a voltage source. An ideal voltage source has zero output impedance, so that the voltage doesn't drop under load. It shouldn't be shorted, because in theory there would flow an infinite current.

An ideal current source has infinite output impedance. This means that the load's impedance is negligible and won't influence the current flowing. Like voltage sources shouldn't be shorted, current sources shouldn't be left open. An open current source will still try to source the set current, and the theoretical current source will go to infinite voltage.

after this conclusion the  option (a)series is the right answer.

Answer 2

A practical current source has input impedance in B) parallel. A practical current source could be represented with a resistor in parallel with an ideal current source.

Explanation:

• A real-world voltage has a very low, but non-zero output impedance is often much less than 1 ohm.
• Conversely, a current source provides a constant current, as long as the load connected to the source terminals has sufficiently low impedance.
• A practical current source is a two terminal device having some resistance connected across its terminals.
• A practical current source is usually represented by a resistance in parallel with an ideal current source.