RC time constant calculator
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Result
Time constant τ470 ms
Capacitor voltage5.662 V
Charged47.18 %
Practically full (5τ)2350 ms
Step-by-step solution
Time constant
τ = R·C = 10 kΩ · 47 µF = 470 ms
Charging an empty capacitor
vC(t) = Vs·(1 − e−t/τ)
vC = 12·(1 − e−300/470) = 5.662 V
Key formulas
- Time constant
- τ = RC | τ = L/R
- Response
- x(t) = x(∞) + [x(0) − x(∞)]·e−t/τ
- Capacitor at DC
- open circuit; vC cannot jump
- Inductor at DC
- short circuit; iL cannot jump
- Settled
- t ≈ 5τ
Practise RC & RL transients
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