Answer / mister smarty pants

Positive feedback is typically part of an an amplifier
circuit where some (or all) of the output of the amplifier
is returned to the input in-phase with the incoming signal.
If enough signal is fed back, it typically causes
oscillation. Positive feedback can occur by virtue of the
inter-component capacitance as a result of poor circuit
design.

Negative feeback is similar except the signal fed back is
in the opposite phase of the original signal coming into
the amplifier. If the amount of negative feedback is
correct, it will typically cancell out any positive
feedback and stabilize an amplifier by preventing
oscillation. This is sometimes also called "neutralizing"
an amplifier.

Answer / mohamed rafik

Negative feedback is used to describe the act of reversing any discrepancy between desired and actual output. Positive feedback responds to a variance between desired and actual output by increasing that variance

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