Fixed Voltage Charge-Energy Three-Row Scan - Electric Fields, Electrostatics & Capacitors Step by Step

At fixed voltage, larger capacitance stores more charge and more energy, so the charge and energy columns rise together row by row. With 6 V held fixed, 1, 2, and 4 F store 6, 12, and 24 C and 18, 36, and 72 J exactly for the ideal capacitor model; real capacitors add tolerance, leakage, dielectric absorption, ESR, voltage rating limits, heating, parasitics, and voltage/charge/energy measurement uncertainty.

At fixed voltage, capacitance controls both stored charge and stored energy through exact row-by-row budgets. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.

highlighted = computed this step

Hold voltage fixed and scan capacitance

Keep the source voltage fixed at 6 volts. A larger capacitance stores more charge at the same voltage, and the energy ledger rises with the same capacitance factor.

Q=CV\qquad U=\tfrac{1}{2}CV^{2}

The charge and energy columns rise together

Read each row left to right: capacitance times the fixed voltage gives charge, then one-half capacitance times voltage squared gives stored energy.

\begin{array}{c|c|c|c}C&V&Q&U\\1\ \text{F}&6\ \text{V}&6\ \text{C}&18\ \text{J}\\2\ \text{F}&6\ \text{V}&12\ \text{C}&36\ \text{J}\\4\ \text{F}&6\ \text{V}&24\ \text{C}&72\ \text{J}\\\end{array}

The checked row closes before rendering

The middle row is not a caption estimate. Its displayed capacitance, charge, voltage, and energy are the same checked quantities used by the table.

C=2\ \text{F}\qquad Q=12\ \text{C}\qquad U=36\ \text{J}