Define negative and positive feedback

1 Answer

Answer :

1. Negative feedback: Feedback in which feedback signal is out of phase with input signal and it decreases output is called negative feedback. 

2. Positive feedback: Feedback in which feedback signal is in phase with input signal and it increases output is called positive feedback. 

Related questions

Description : Write advantages and disadvantages of positive and negative feedback.

Last Answer : Advantages of Positive Feedback: i) Voltage gain increases. ii) No phase shift is provided. iii) Feedback signal and input signal are in phase. iv) Input and Output voltage increases.  ... ii) Feedback signal and input signal are out of phase. iii) Input and Output voltage decreases.

Description : Differentiate between positive and negative feedback.

Last Answer : PARAMETER POSITIVE FEEDBACK NEGATIVE FEEDBACK Overall phase shift 0° or 360° 180° Feedback and input signal Are in phase Are out of phase Input signal ... Increases Input impedance Decreases Increases Output impedance Increases Decreases

Description :  advantages of negative feedback over positive feedback.

Last Answer : Advantages of negative feedback over positive feedback: 1. Higher fidelity i.e. more linear operation. 2. Highly stabilized gain. 3. Increased bandwidth i.e. improved frequency response. 4. Less ... . 8. Input and output impedance can be modified as desired. 9. Less frequency distortion.

Description : Compare positive and negative feedback.

Last Answer : Sr. No. Parameter Positive feedback  Negative feedback 1 BW Increases Decreases 2 Feedback signal In phase with the input signal. 180 º out of phase ... impedance increases decreases 9 Uses Oscillators, Schmitt trigger Amplifiers, bootstrapping

Description : Is an anode positive or negative?

Last Answer : The anode is positively charged electrode.

Description : The effect of negative feedback on distortion and bandwidth is A) Both distortion and bandwidth get decreased B) Both distortion and bandwidth get increased C) Distortion is reduced and bandwidth is increased D) Distortion is increased and bandwidth is decreased 

Last Answer : The effect of negative feedback on distortion and bandwidth is Distortion is reduced and bandwidth is increased

Description : An amplifier has a voltage gain of 120. To reduce distortion, 10% negative feedback is employed. The gain of the amplifier with feedback is  (1) 141 (2) 92.3 (3) 9.23 (4) 1.41

Last Answer : An amplifier has a voltage gain of 120. To reduce distortion, 10% negative feedback is employed. The gain of the amplifier with feedback is 9.23

Description : A unity negative feedback control system is found to have a gain margin of 20 dB. The Nyquist plot of the system (A) crosses the real axis at +0.1 (B) crosses the real axis at -0.1. (C) crosses the imaginary axis at -0.1 (D) crosses the imaginary axis at +0.1

Last Answer : A unity negative feedback control system is found to have a gain margin of 20 dB. The Nyquist plot of the system crosses the real axis at -0.1.

Description : Negative feedback in a closed-loop control system DOES NOT (A) reduce the overall gain (B) reduce bandwidth (C) improve disturbance rejection (D) reduce sensitivity to parameter variation

Last Answer : Negative feedback in a closed-loop control system DOES NOT reduce bandwidth

Description : Can the electric field between two positive charges be zero?

Last Answer : It  can  only  if  they  have  equal  charges.

Description : different types of feedback amplifiers

Last Answer : Types of feedback amplifiers: 1. Positive feedback amplifiers 2. Negative feedback amplifiers (i)voltage series feedback amplifiers (ii)voltage shunt feedback amplifiers (iii)current series feedback amplifiers (iv)current shunt feedback amplifiers

Description : Do you have a positive attitude or a negative one?

Last Answer : I’m an “expect the worst, hope for the best” kind of person.

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Last Answer : It appears I’m using Internet Explorer and your website made my computer freeze. I had to open Task Manager and end the program to get back up and running.

Description : What do you do to find trustworthy feedback?

Last Answer : Look them in the eye in a confident way and say “Don’t lie to me. Be honest.” Usually works for me.

Description : I'm an aspiring author. Is there anyone out there that would like to read my manuscript and give me honest feedback?

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Last Answer : Given a unity feedback system with G(s)=k/s (s+4), the value of k for damping ratio of 0.5 is 16

Description : Why is the phrase "Two can play at that game!" always referring to something negative?

Last Answer : That’s not what he meant last night. (waggle, waggle)

Description : A negative sequence relay is used for protection of  (1) Generator (3) Motor (2) Transformer (4) Long Transmission lines

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Description : A transformer has negative voltage regulation when its load power factor is   (1) Zero (2) Unity (3) Leading (4) Lagging

Last Answer : 0

Description : Which diode exhibits negative resistance characteristic? (A) LED (B) Zener (C) Tunnel diode (D) PN diode

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Description : The transducer with negative temperature co-efficient of resistance is (A) Thermistor (B) Resistance Thermometer (C) Strain Gauge (D) Thermocouple

Last Answer : The transducer with negative temperature co-efficient of resistance is Thermistor

Description : Negative voltage regulation is indicative that the load is?

Last Answer : Negative voltage regulation is indicative that the load is capacitive.

Description : Which side of a capacitor is negative?

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Description : Define: 1) Electrode 2) Electrolyte

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Description : Define earthing. State its types.  

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Description : Define Resonance. 

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Description : Define Electrical Installation and give its classification.

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Description : Define laminar flow and turbulent flow.

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Description : Define natural, mechanical, forced and induced draught systems.

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Description : Define the term solar constant.

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Description : Define Q factor.

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Description : Define energy. Write unit of it.

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Description : Define accuracy and precision

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Description : Define biasing of transistor

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Description : Define load and line regulation.

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Description : Define pinch off voltage and drain resistance of FET.

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Description : Define ripple factor and PIV of diode.

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Description : Define Depletion region and Barrier voltage of PN junction.

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