🔍 Key Concepts

• How resistances in series combine into an equivalent resistance • How capacitances in series combine into an equivalent capacitance • The formula for the RC time constant of a circuit

💭 Think About

• First, find the single equivalent resistance of the two 1-megohm resistors in series. What is that value in ohms? • Next, determine the single equivalent capacitance of the two 220-microfarad capacitors in series. Is the result larger or smaller than 220 microfarads? • Finally, use the RC time constant formula with your equivalent R and C values and convert microfarads and megohms to base SI units before multiplying.

✅ Before You Answer

• Be sure you treated the series capacitors correctly (they do NOT add like resistors in series). • Confirm that you converted microfarads to farads and megohms to ohms before multiplying. • After multiplication, check whether the unit of your result is in seconds and whether it matches one of the choices.