Amplifier (non inverting) question

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The discussion centers on calculating the closed loop gain of a non-inverting amplifier with a negative feedback fraction of 0.5% and an open loop gain of 10^5, resulting in a closed loop gain of 199.6. The amplifier is connected to a signal source with an internal resistance of 300kΩ and an amplitude of 30mV. Calculations for output voltage under different load conditions yield specific results: 0.03V for an open circuit, approximately 2V for an 8Ω load, and 0.06V for a 600Ω load, though the latter does not match the provided multiple-choice options.

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Homework Statement


An amplifier has negative feedback applied to it such that feedback fraction is 0.5%. If the open loops gain of the amplifier is 10^5 what is the closed loop gain? I get this as 199.6

The amplifier is connected to a signal source of internal resistance 300kohms which provides a sinusoidal signal of 30mV amplitude, when not loaded. If the amplifier has an input resistance of 150kohms and an output resistance of 600ohms what is the amplitude of the voltage signal that would appear at the output terminals of the amplifier when it is
a) open circuit
b) connected to a load resistance of 8 ohms
c) connected to a load resistance of 600 ohms

Homework Equations


Gain of a non inverting amplifier = (R1+R2)/2

Any help would be great. It's multiple choice and the options are parts a,b and c are;

0.003V, 0.03V, 0.3V, 1V, 2V
 
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Can anyone help?
 

Homework Statement


An amplifier has negative feedback applied to it such that feedback fraction is 0.5%. If the open loops gain of the amplifier is 10^5 what is the closed loop gain? I get this as 199.6

The amplifier is connected to a signal source of internal resistance 300kohms which provides a sinusoidal signal of 30mV amplitude, when not loaded. If the amplifier has an input resistance of 150kohms and an output resistance of 600ohms what is the amplitude of the voltage signal that would appear at the output terminals of the amplifier when it is
a) open circuit
b) connected to a load resistance of 8 ohms
c) connected to a load resistance of 600 ohms

Homework Equations


Gain of a non inverting amplifier = (R1+R2)/R2

Any help would be great. It's multiple choice and the options are parts a,b and c are;

0.003V, 0.03V, 0.3V, 1V, 2V

The Attempt at a Solution


a) open circuit, R1 = 0, R2 = infinity so gain is 1 ==> Vout = 0.03
b) Gain = (600+8)/8 = 76 => Vout is approximately 2
c) Gain = (600+600)/600 = 2 ==> Vout is 0.06 but there isn't an option for this. :S
Attempt
a) open circuit, R1 = 0, R2 = infinity so gain is 1 ==> Vout = 0.03
b) Gain = (600+8)/8 = 76 => Vout is approximately 2
c) Gain = (600+600)/600 = 2 ==> Vout is 0.06 but there isn't an option for this. :S

Could someone help?
I've shown my working.
 

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