In many electronic circuits in which some kind of time scale is involved, such as filters and

Question:

In many electronic circuits in which some kind of time scale is involved, such as filters and time-delay circuits (Fig. P7–109—a low-pass filter), you often see a resistor (R) and a capacitor (C) in series. In fact, the product of R and C is called the electrical time constant, RC. Showing all your work, what are the primary dimensions of RC? Using dimensional reasoning alone, explain why a resistor and capacitor are often found together in timing circuits.

FIGURE P7–109