Capacitance to Charge Calculator
Evaluate the total electrostatic charge (Q) in Coulombs stored on a capacitor given its capacitance (C) and applied potential difference (V). Settle dielectric nodes dynamically.
Capacitance to Charge Calculator
How to Use the Capacitance to Charge Calculator
Calculating the total electric charge held by a capacitor is straightforward. Follow these steps:
- 1Enter Capacitance: Input the physical capacitance value of the capacitor.
- 2Select Capacitance Unit: Choose Farad (F), millifarad (mF), microfarad (µF), nanofarad (nF), or picofarad (pF).
- 3Enter Voltage: Input the potential difference applied across the capacitor terminals.
- 4Select Voltage Unit: Choose Volts (V), millivolts (mV), or kilovolts (kV).
- 5Calculate: Click the "Calculate to Charge" button to run the conversion.
How to Calculate Capacitance to Charge
In electrical engineering, a capacitor stores electric charge on its opposing plates when subjected to an applied voltage. The total stored electrostatic charge (Q) in Coulombs is directly proportional to both the capacitance (C) in Farads and the applied potential difference (V) in Volts. When voltage is constant, a higher capacitance stores more charge. The charge calculation uses the base unit conversion rules of physics before multiplication.
Real-Life Sizing Scenarios
Scenario 1: Sizing Charge for a 4 µF Capacitor Charged to 100 V
An electronics designer calculates the total charge stored in a 4 µF coupling capacitor charged to a potential difference of 100 V:
Q = C × V = (4 × 10^−6 F) × 100 V = 0.0004 Coulombs (or 0.4 mC / 400 µC)
Scenario 2: Sizing Charge for a 1.5 F Power Capacitor Charged to 400 V
A power technician checks the charge on a bank capacitor rated at 1.5 Farads charged up to 400 Volts:
Q = C × V = 1.5 F × 400 V = 600 Coulombs
Step-by-Step Manual Sizing Guide
- 1Identify component parameters: Settle the capacitance (C) and the voltage (V).
- 2Convert to base physical units: Convert capacitance to Farads (F) (e.g. 10 µF = 10 × 10^−6 F) and voltage to Volts (V).
- 3Multiply the metrics: Apply the capacitor formula
Q = C × Vto find the stored charge.
Capacitance to Charge Conversion Chart
The table below displays standard capacitance ratings and their corresponding stored charge values in Coulombs (C) at typical voltage levels (12 V and 120 V):
| Capacitance Input | Voltage Level | Stored Charge (at 12 V) | Stored Charge (at 120 V) |
|---|---|---|---|
| 1.0 µF | 12 V / 120 V | 0.000012 C (12 µC) | 0.00012 C (120 µC) |
| 4.0 µF | 12 V / 120 V | 0.000048 C (48 µC) | 0.00048 C (480 µC) |
| 10.0 µF | 12 V / 120 V | 0.000120 C (120 µC) | 0.00120 C (1.2 mC) |
| 47.0 µF | 12 V / 120 V | 0.000564 C (564 µC) | 0.00564 C (5.64 mC) |
| 100.0 µF | 12 V / 120 V | 0.001200 C (1.2 mC) | 0.01200 C (12 mC) |
| 470.0 µF | 12 V / 120 V | 0.005640 C (5.64 mC) | 0.05640 C (56.4 mC) |
| 1000.0 µF | 12 V / 120 V | 0.012000 C (12 mC) | 0.12000 C (120 mC) |
| 2200.0 µF | 12 V / 120 V | 0.026400 C (26.4 mC) | 0.26400 C (264 mC) |
A Capacitor of Capacitance 4µF Is Charged to 100V
To calculate the charge on this capacitor, apply the standard conversion formula: Q = C × V. Convert 4 µF to Farads (4 × 10^−6 F) and multiply by 100 V to locate the charge:
Q = (4 × 10^−6 F) × 100 V = 0.0004 Coulombs (or 0.4 millicoulombs / 400 microcoulombs).
Is Capacitance Directly Proportional to Charge
Capacitance itself is a geometric constant of the physical capacitor, defined as C = Q ÷ V. Thus, capacitance does not increase when charge increases. Instead, for a fixed capacitor rating, the stored electric charge is directly proportional to the applied voltage across its plates.
A Capacitor of Capacitance C Is Charged to A
When a capacitor of capacitance C is charged to a potential difference V, it stores electrostatic charge Q = C × V and holds energy E = 0.5 × C × V². This energy is stored within the electrostatic field of the dielectric layer.
What Is Charging of Capacitor
Charging of a capacitor is the process where electrons accumulate on one plate and leave the opposing plate, building an electrostatic field. This transient current flow continues until the voltage across the capacitor plates matches the applied source voltage.
Capacitance to Charge Formula
The standard physical formula relates charge (Q) in Coulombs, capacitance (C) in Farads, and voltage (V) in Volts:
Q = C × V
Frequently Asked Questions (FAQs)
To calculate the electric charge, multiply the capacitance value in Farads by the applied voltage in Volts: Q = C × V. Ensure all units are scaled to base Farads before solving.
To convert capacitance to voltage, divide the total stored charge in Coulombs by the capacitance in Farads: V = Q ÷ C.
Multiply the rated capacitance of the component (converted to Farads) by the voltage measured across its terminals to find the total stored charge on the capacitor plates.
Calculate the voltage across the capacitor by dividing the total stored charge (Q) by its rated capacitance (C): V = Q ÷ C.
Capacitance resists changes in voltage. A larger capacitor stabilizes DC voltage lines, filters ripples, and slows down voltage transitions based on the transient charging current: i = C × (dV/dt).
For a constant voltage level, the stored charge is directly proportional to the capacitance. If you double the capacitance of the capacitor, it will hold twice the charge at the same voltage.
The transient charging voltage of a capacitor over time through a series resistor is calculated using: V(t) = V_0 × (1 − e^(−t ÷ RC)), where RC is the circuit time constant.