The capacitor discharge calculator determines the voltage across a capacitor at any given time during its discharge through a resistor.
Formula
The voltage across a discharging capacitor is given by:
$$V_{\text{discharge}} = V_{\text{initial}} \times e^{-t / (R \times C)}$$
Where:
- V_discharge is the voltage at time t
- V_initial is the initial voltage
- t is the time elapsed
- R is the resistance in ohms
- C is the capacitance in farads
Example
For a capacitor with:
- Initial voltage: 12 V
- Time: 5 seconds
- Resistance: 1000 ฮฉ
- Capacitance: 0.002 F
Calculation:
$$V_{\text{discharge}} = 12 \times e^{-5/(1000 \times 0.002)}$$
$$V_{\text{discharge}} = 12 \times e^{-2.5}$$
$$V_{\text{discharge}} \approx 12 \times 0.082$$
$$V_{\text{discharge}} \approx 0.98 \text{ V}$$