Avionics Electronics Technician (AET) Practice Exam - Prep & Study Guide

To find the total capacitance of capacitors connected in parallel, the individual capacitances are simply summed together. This method is based on the principle that in a parallel circuit, the voltage across each capacitor remains the same, while the total current is the sum of the individual currents, which corresponds to the additive nature of capacitance.

For the given capacitors, you have:

- 0.25 microfarads

- 0.03 microfarads

- 0.12 microfarads

By adding these values together:

0.25 + 0.03 + 0.12 = 0.40 microfarads.

Thus, the total capacitance is 0.40 microfarads, which is why this choice is the correct response. This understanding of parallel capacitance, where individual capacitances add directly, is crucial for effective circuit design and analysis in avionics systems where capacitance plays a significant role in filtering and energy storage.