Question 1

How do I calculate capacitor charge and energy?

Accepted Answer

Use Q = C·V for charge and E = 1/2·C·V^2 for stored energy.

Question 2

What is capacitive reactance?

Accepted Answer

Xc = 1/(2πfC) describes a capacitor’s opposition to AC; it decreases as frequency increases.

Question 3

How do capacitors combine?

Accepted Answer

In parallel: C_total = ΣC. In series: 1/C_total = Σ(1/C).

Question 4

What is the RC time constant?

Accepted Answer

τ = R·C; it sets the speed of charge/discharge: V(t) = Vs·(1 - e^(−t/RC)) for charging.

Question 5

Any safety considerations?

Accepted Answer

Respect voltage ratings and discharge capacitors before handling; high-voltage capacitors can retain a dangerous charge.

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