Engine: Electricity

1. A The RC coupling functions as a filter by removing the DC component from the varying DC input to produce an AC output shifted 90 from the input.
2. B The RC coupling functions as a filter by removing the DC component from the varying DC input to produce an AC output shifted 180 from the input.
3. C The RC coupling functions as a filter by removing the DC component from the varying DC input to produce an AC output in phase with the input.
4. D The RC coupling functions as a voltage transformer by changing the magnitude of the peak to peak AC voltage at the output proportional to the RC time constant.

Tip: press A-D to answer