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Formula Charging capacitor Capacitor current    Capacitance    Resistance    Time

Formula
Formula: Charging capacitor
RC Circuit - charging capacitor
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Capacitor current

Unit
Capacitor current is the electric current that flows into the plate of the capacitor and thus builds up a voltage on the capacitor. This capacitor current decreases exponentially with time during the charging process, while the capacitor voltage \( U(t) \) increases exponentially.

Charging current

Unit
Charging current is the initial current that flows into the capacitor plate at time \( t = 0 \). Its value is given by the applied source voltage.

Capacitance

Unit
Electrical capacitance is a characteristic quantity of the capacitor and tells how many charges must be brought onto the capacitor to charge the capacitor to the voltage \( 1 \, \text{V} \).

Resistance

Unit
Resistor with resistance \( R \) connected in series with the capacitor. The resistor has an influence on how fast the capacitor can charge.

Time

Unit
After the source voltage \(U_0\) is applied (switch is closed), the capacitor starts to charge. The charging current starts to flow through the circuit and decays over time \(t\).