Operational amplifier with feedback problem

[TheRedDevil18]

Homework Statement

Homework Equations

The Attempt at a Solution

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Using the equations above, I'm not getting the right answer for beta which is 0.4926 V/A.
Is my model wrong ?

 

[NascentOxygen]

The op-amp's r_o should be shown in series with the controlled voltage source.

 

[TheRedDevil18]

The op-amp's r_o should be shown in series with the controlled voltage source.

So with a voltage source, ro is always in series ?

 

[NascentOxygen]

So with a voltage source, ro is always in series ?

Yes.

If you were to place a resistance in parallel with an ideal voltage source, what would be the Thévenin equivalent resistance of that combination?

 

[TheRedDevil18]

Yes.

If you were to place a resistance in parallel with an ideal voltage source, what would be the Thévenin equivalent resistance of that combination?

Would it be a voltage source in series with the resistance ?, I know that a current source with a parallel resistance is equal to a voltage source in series with that resistance

 

[NascentOxygen]

Would it be a voltage source in series with the resistance ?

Guessing is not allowed.

Can you determine it?

 

[TheRedDevil18]

Guessing is not allowed.

Can you determine it?

Would it be zero ?, I determined it by using the rules. When you have a voltage source you short it and remove the load, so that means all the current will flow through the short and not through the parallel resistor

 

[NascentOxygen]

Would it be zero ?, I determined it by using the rules. When you have a voltage source you short it and remove the load, so that means all the current will flow through the short and not through the parallel resistor

Right. A resistance has no effect if you erroneously add it parallel to an ideal voltage source: the effective source resistance here would stay as zero.

 

[TheRedDevil18]

Right. A resistance has no effect if you erroneously add it parallel to an ideal voltage source: the effective source resistance here would stay as zero.

Ok, thanks, I'll attempt the question again