Question
Physics Question on Oscillations
The positive feedback is required by an amplifier to act an oscillator. The feedback here means:
External input is necessary to sustain ac signal in output
A portion of the output power is returned back to the input
Feedback can be achieved by LR network
The base-collector junction must be forward biased
A portion of the output power is returned back to the input
Solution
The correct answer is (B): A portion of the output power is returned back to the input
Explanation:
Feedback means a portion of the output power is fed to the inputs.
Positive feedback involves taking a fraction of the output signal and introducing it back into the input, often in phase with the input signal. This can result in a cumulative effect, where the signal keeps reinforcing itself, leading to sustained oscillations.