1 Answer
Positive and negative feedback are two different mechanisms used in systems (like amplifiers, control systems, and biological processes) to regulate their behavior. Here’s the difference in simple terms:
1. Positive Feedback:
- What happens: Positive feedback amplifies or increases the output of the system. When a change happens, it gets reinforced, leading to a larger change.
- Effect: The system "feeds back" into itself to continue the process in the same direction.
- Example: Think of a microphone close to speakers. If the microphone picks up sound from the speakers, it amplifies it more, which makes the sound louder, and the microphone picks up even more sound, creating a loop that grows until it becomes uncontrollable (this is why you hear a loud screeching noise).
- In summary: Positive feedback creates an escalating effect. It moves things further from equilibrium.
2. Negative Feedback:
- What happens: Negative feedback reduces or counteracts changes, helping the system return to its stable state. It works to maintain balance.
- Effect: The system "feeds back" to correct itself and keep the output in check.
- Example: A thermostat is a great example. If the room temperature gets too high, the thermostat detects the change and turns the heater off, reducing the temperature. When the temperature gets too low, the thermostat turns the heater back on. It keeps the temperature stable.
- In summary: Negative feedback stabilizes the system by reducing or opposing any changes.
Key Difference:
In most natural and engineering systems, negative feedback is more common because it stabilizes the system, while positive feedback is less common and usually occurs in specific situations where amplification is needed (like in some biological processes).
1. Positive Feedback:
- What happens: Positive feedback amplifies or increases the output of the system. When a change happens, it gets reinforced, leading to a larger change.- Effect: The system "feeds back" into itself to continue the process in the same direction.
- Example: Think of a microphone close to speakers. If the microphone picks up sound from the speakers, it amplifies it more, which makes the sound louder, and the microphone picks up even more sound, creating a loop that grows until it becomes uncontrollable (this is why you hear a loud screeching noise).
- In summary: Positive feedback creates an escalating effect. It moves things further from equilibrium.
2. Negative Feedback:
- What happens: Negative feedback reduces or counteracts changes, helping the system return to its stable state. It works to maintain balance.- Effect: The system "feeds back" to correct itself and keep the output in check.
- Example: A thermostat is a great example. If the room temperature gets too high, the thermostat detects the change and turns the heater off, reducing the temperature. When the temperature gets too low, the thermostat turns the heater back on. It keeps the temperature stable.
- In summary: Negative feedback stabilizes the system by reducing or opposing any changes.
Key Difference:
- Positive feedback drives the system further away from its starting point or equilibrium.
- Negative feedback works to bring the system back to its equilibrium or set point.
In most natural and engineering systems, negative feedback is more common because it stabilizes the system, while positive feedback is less common and usually occurs in specific situations where amplification is needed (like in some biological processes).