Capacitor Discharge Calculator

Calculate and visualize RC circuit decay with our Capacitor Discharge Calculator. Get instant results for time constants (τ) and exponential voltage drop.

Circuit Parameters

V
Time Constant (τ): 1.00 ms
Full Discharge (5τ): 5.00 ms

Understanding the Concepts

What is Capacitor Discharge?

When a charged capacitor is connected to a resistor, it begins to release its stored electrical energy, creating a current that flows through the resistor. This process is called discharging. The voltage across the capacitor doesn't drop instantly; it decreases exponentially over time. This interactive tool helps you visualize and calculate this decay.

The Time Constant (τ)

The time constant, represented by the Greek letter tau (τ), is a crucial measure in an RC circuit. It's calculated as the product of resistance (R) and capacitance (C): τ = R × C. The time constant represents the time it takes for the capacitor's voltage to drop to approximately 36.8% of its initial value. It effectively defines the speed of the discharge process.

Simple RC Discharge Circuit

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-
C
R

Capacitor (C) discharging through a Resistor (R).

The Discharge Formula

The voltage V across the capacitor at any given time t during discharge is calculated using the formula:

V(t) = V₀ * e-t/RC

Where V₀ is the initial voltage, R is the resistance, C is the capacitance, and 'e' is the base of the natural logarithm (approximately 2.718).

Frequently Asked Questions

Built as an interactive educational tool. Calculations are for illustrative purposes.

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