Capacitor in DC and AC Circuits
This simulation demonstrates how a lamp behaves when connected in series with a capacitor under DC and AC power:
DC Circuit
AC Circuit
Physics Explanation:
DC Connection:
- Capacitor charges quickly and acts as an open circuit
- No continuous current flows after initial charging
- Lamp doesn't glow (or flashes briefly during charging)
- Reducing capacitance makes no difference to steady state
AC Connection:
- Capacitor continuously charges and discharges
- Current flows due to capacitive reactance \( X_C = \frac{1}{\omega C} \)
- Lamp glows continuously
- Reducing capacitance increases reactance, reducing current and lamp brightness
Capacitive Reactance: \( X_C = \frac{1}{2\pi f C} \)
Key Observations:
- DC: Lamp off (capacitor blocks DC after charging)
- AC: Lamp on (capacitor allows AC current to flow)
- Lower capacitance ⇒ Higher reactance ⇒ Dimmer lamp (AC only)
