What is the frequency of the dc signal

Answer:  Since there is only one direction of current flow, the frequency of direct current (DC) is zero. There is no room for direction reversal, and the frequency of direct current (DC) is always zero.

In addition, the magnitude of the current generated by a DC power source is always constant, whereas that created by an AC power source is always changeable.

Direct current indicates that the passage of charge is unidirectional. Electrons go from negative to positive in a battery, while direct current flows from positive to negative.

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