Shifting the phase of an ac sine wave by 90 degrees is the same thing as ___

Shifting the phase of an ac sine wave by 90 degrees is the same thing as:

A. Moving it to the right or left by a full cycle.
B. Moving it to the right or left by 1⁄4 cycle.
C. Turning it upside-down.
D. Leaving it alone.

Show Answer

Answer: B

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