Willy Nilly, a peripatetic EE grad student, has a problem.  He has been trying to help his advisor set up an op-amp experiment.  Here is what he has done, step-by-step.

1.  He set up a function generator to provide a sine wave at 1000 Hz.

2.  Using an oscilloscope, he carefully set the sine wave to have
     an amplitude of 0.10v (0.20v peak-to-peak).

3.  He wants to demonstrate an operational amplifier circuit with a
     high gain, so he wired up the circuit below.

     The values he chose were:

               R₁ = 50W.
                R₀ = 5000W.

     According to his calculations this gives a gain of -100.

4.  He calculates that with a gain of -100, he should get an output
     signal that is 10v amplitude (20v peak-to-peak).

5.  He measures the output of the operational amplifier.  The measured
     signal is 5v amplitude (10v peak-to-peak).  This is not what he
     expected!

6.  Although the output of the operational amplifier is not what he
     expected, the input and output voltages are 180^o out of phase,
     as expected.

        Willy is at a loss.  He has repeated all of the above steps several times, and he cannot understand why the output is not what he expects it to be.

Your problem:  You need to explain to Willy what is going on.