--- title: Ohm's Law Calculator — Voltage, Current, Resistance, Power & Resistor Networks | CalcWorkBench description: Free Ohm's Law Calculator, Power Triangle & Resistor Network Calculator. Solve the 12-formula Ohm's Law wheel (V, I, R, P), series and parallel resistor networks, voltage dividers, and AC/3-phase complex impedance with real-time vector diagrams. image: https://calcworkbench.com/assets/calcworkbench_icon.jpg --- # Ohm's Law, Power & Resistor Network Calculator Free Ohm's Law, Power & Resistor Network Calculator for DC circuits, resistor ladder networks, voltage dividers, and AC complex impedance ($Z = R + jX$). - **Canonical URL:** https://calcworkbench.com/calculators/ohms-law-calculator.html - **Markdown Version:** https://calcworkbench.com/calculators/ohms-law-calculator.md --- ## 1. The 12 Ohm's Law & Power Formulas (Wheel / Circle Chart) Ohm's Law and Joule's Law define the proportional relationship between electric potential difference, charge flow, resistance, and continuous power dissipation ($V = I \times R$, $P = V \times I$). Given any two known variables among Voltage ($V$), Current ($I$), Resistance ($R$), and Power ($P$), the remaining two are calculated via: | Target Metric | Formula from $V, I$ | Formula from $I, R$ | Formula from $V, R$ | Formula from $P, I$ | Formula from $P, V$ | Formula from $P, R$ | SI Unit | | :--- | :--- | :--- | :--- | :--- | :--- | :--- | :--- | | **Voltage ($V$)** | — | $V = I \times R$ | — | $V = \frac{P}{I}$ | — | $V = \sqrt{P \times R}$ | Volts (V) | | **Current ($I$)** | — | — | $I = \frac{V}{R}$ | — | $I = \frac{P}{V}$ | $I = \sqrt{\frac{P}{R}}$ | Amperes (A) | | **Resistance ($R$)** | $R = \frac{V}{I}$ | — | $R = \frac{V^2}{P}$ | $R = \frac{P}{I^2}$ | — | — | Ohms ($\Omega$) | | **Power ($P$)** | $P = V \times I$ | $P = I^2 \times R$ | $P = \frac{V^2}{R}$ | — | — | — | Watts (W) | --- ## 2. Resistor Networks, Dividers & Attenuator Topologies To calculate Ohm's law in a series circuit, add resistances directly ($R_{eq} = R_1 + R_2 + \dots$) because current is uniform; to calculate Ohm's law in a parallel circuit, sum reciprocal conductances ($1/R_{eq} = 1/R_1 + 1/R_2 + \dots$) because voltage is identical across every branch. | Topology | Equivalent Resistance Formula | Current / Voltage Behavior | Application | | :--- | :--- | :--- | :--- | | **Series Chain** | $R_{eq} = \sum R_i = R_1 + R_2 + \dots + R_n$ | $I_1 = I_2 = I_{total}$; $V = \sum V_i$ | Current limiting, sensing shunts | | **Parallel Bank** | $\frac{1}{R_{eq}} = \sum \frac{1}{R_i} \iff \frac{R_1 \times R_2}{R_1 + R_2}$ | $V_1 = V_2 = V_{source}$; $I = \sum I_i$ | Power sharing, speaker loads | | **Voltage Divider** | $V_{out} = V_{in} \times \left(\frac{R_2}{R_1 + R_2}\right)$ | Proportionally divides input voltage | ADC sensor scaling, bias networks | | **R-2R Ladder** | $R_{in} = R$ (constant) | Binary-weighted stage current splitting | DAC conversion, resistor arrays | | **Pi ($\pi$) Attenuator** | $R_1 = Z_0 \frac{10^{dB/20} + 1}{10^{dB/20} - 1}$ | Shunt-Series-Shunt matching network | RF transmission, 50$\Omega$ / 75$\Omega$ pads | | **Tee (T) Attenuator** | $R_{series} = Z_0 \frac{10^{dB/20} - 1}{10^{dB/20} + 1}$ | Series-Shunt-Series symmetrical net | Audio/RF signal attenuation pads | --- ## 3. AC Complex Impedance & The Power Triangle The AC power triangle calculates the vector relationship between Real Power ($P$ in Watts), Reactive Power ($Q$ in VAR), and Apparent Power ($S$ in VA) through the Pythagorean formula $S^2 = P^2 + Q^2$, where the power factor ($\text{PF} = \cos\theta = P/S$) defines overall efficiency. $$Z = R + jX = |Z| \angle \theta$$ - **Magnitude:** $|Z| = \sqrt{R^2 + X^2}$ - **Phase Angle:** $\theta = \arctan\left(\frac{X}{R}\right)$ - **Admittance:** $Y = \frac{1}{Z} = G + jB$ ### Single-Phase & Balanced 3-Phase Equations | Power Metric | Single-Phase ($1\phi$) | Balanced 3-Phase ($3\phi$) | Engineering Units | | :--- | :--- | :--- | :--- | | **Real Power ($P$)** | $P = V_{rms} I_{rms} \cos(\theta)$ | $P = \sqrt{3} V_{LL} I_L \cos(\theta)$ | Watts (W / kW) | | **Reactive Power ($Q$)** | $Q = V_{rms} I_{rms} \sin(\theta)$ | $Q = \sqrt{3} V_{LL} I_L \sin(\theta)$ | VAR / kVAR | | **Apparent Power ($S$)** | $S = V_{rms} I_{rms} = \sqrt{P^2 + Q^2}$ | $S = \sqrt{3} V_{LL} I_L$ | Volt-Amperes (VA / kVA) | | **Power Factor (PF)** | $\text{PF} = \cos(\theta) = \frac{P}{S}$ | $\text{PF} = \cos(\theta) = \frac{P}{S}$ | Dimensionless (0.0 to 1.0) | | **Correction Capacitance ($Q_c$)** | $Q_c = P [\tan(\theta_1) - \tan(\theta_2)]$ | $C_{Delta} = \frac{Q_c}{3 \times 2\pi f V_{LL}^2}$ | kVAR / uF | --- ## 4. Practical Circuit Applications ### Sizing Current-Limiting Resistors for LEDs $$R = \frac{V_{source} - V_{forward}}{I_{desired}}$$ - For a 12V supply powering a 2V LED at 20mA ($0.02A$): $R = (12 - 2) / 0.02 = 500\,\Omega$. - Resistor power dissipation: $P = I^2 R = (0.02)^2 \times 500 = 0.20\text{ W}$ (requires a 1/2-Watt rated resistor). ### Audio Speaker Impedance - Two $8\,\Omega$ speakers wired in parallel present a $4\,\Omega$ equivalent load ($R_{eq} = (8 \times 8) / (8 + 8) = 4\,\Omega$). - Amplifier wattage output scales inversely with impedance: $P = V^2 / R$. --- ## 5. Frequently Asked Questions ### What is Ohm's Law and how do you calculate it? Ohm's Law states that electric current flowing through a conductor between two points is directly proportional to voltage and inversely proportional to resistance: $V = I \times R$. To calculate voltage, multiply current by resistance ($V = I \times R$); to calculate current, divide voltage by resistance ($I = V / R$); and to calculate resistance, divide voltage by current ($R = V / I$). ### How do you calculate power and find watts using Ohm's Law? To calculate electrical power in Watts using Ohm's Law and Joule's Law, multiply voltage by current: $P = V \times I$. If current and resistance are known, power equals $I^2 \times R$; if voltage and resistance are known, power equals $V^2 / R$. ### How do you calculate Ohm's Law in a series circuit? To calculate Ohm's law in a series circuit, add all resistances directly ($R_{eq} = R_1 + R_2 + \dots$) because current remains identical through every series component. Total current is $I = V_{total} / R_{eq}$, and individual voltage drops equal $V_i = I \times R_i$. ### How do you calculate Ohm's Law in a parallel circuit? To calculate Ohm's law in a parallel circuit, sum reciprocal conductances ($1/R_{eq} = 1/R_1 + 1/R_2 + \dots$) because voltage is identical across every parallel branch. Branch currents divide according to $I_i = V / R_i$. ### What is the formula for calculating the Power Triangle? The fundamental formula for calculating the power triangle is the right-triangle relation $S^2 = P^2 + Q^2$, where $S$ is Apparent Power in Volt-Amperes (VA), $P$ is Real Power in Watts (W), and $Q$ is Reactive Power in Volt-Amperes Reactive (VAR). ```json { "@context": "https://schema.org", "@graph": [ { "@type": "WebApplication", "@id": "https://calcworkbench.com/calculators/ohms-law-calculator.html#webapp", "name": "Ohm's Law, Power & Resistor Network Calculator", "url": "https://calcworkbench.com/calculators/ohms-law-calculator.html", "applicationCategory": "EducationalApplication", "operatingSystem": "All", "browserRequirements": "Requires JavaScript and HTML5 SVG support", "description": "Interactive electrical calculator featuring a complete Ohm's Law wheel solver, mixed series/parallel resistor network ladder solver, and AC complex impedance (R + jX) analyzer with dynamic power triangle visualization.", "offers": { "@type": "Offer", "price": "0", "priceCurrency": "USD" }, "featureList": [ "2-of-4 Ohm's Law Wheel solver covering all 12 circle formulas for Voltage, Current, Resistance, and Power", "Mixed series and parallel resistor network ladder solver with voltage and power dissipation breakdowns", "AC complex impedance analyzer in rectangular (R + jX) and polar (|Z|\u2220\u03b8) representations", "Real-time AC Power Triangle visualization showing Real Power (P), Reactive Power (Q), and Apparent Power (S)", "Three-phase AC power triangle and balanced load calculations", "Power Factor (PF) correction capacitor sizing in kVAR and microfarads (\u00b5F)", "Interactive SVG diagrams with logarithmic sliders and SI engineering units", "Printable reference tables and semantic formula charts for engineering reference" ], "potentialAction": { "@type": "ConsumeAction", "target": { "@type": "EntryPoint", "urlTemplate": "https://calcworkbench.com/calculators/ohms-law-calculator.html?mode={mode}&val1={val1}&val2={val2}", "actionPlatform": [ 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"parameters": { "type": "object", "properties": { "mode": { "type": "string", "enum": [ "wheel", "resistor_network", "ac_power_triangle" ], "description": "Calculation mode: 'wheel' for 2-of-4 Ohm's Law wheel solver, 'resistor_network' for series/parallel combinations and voltage divider ladders, or 'ac_power_triangle' for AC complex impedance and power triangle analysis." }, "wheel_parameters": { "type": "object", "properties": { "known_pair": { "type": "string", "enum": [ "vi", "vr", "vp", "ir", "ip", "rp" ], "description": "The known pair of electrical metrics: 'vi' (voltage & current), 'vr' (voltage & resistance), 'vp' (voltage & power), 'ir' (current & resistance), 'ip' (current & power), 'rp' (resistance & power)." }, "voltage": { "type": "number", "description": "Electric potential difference in Volts (V)." }, "current": { "type": "number", "description": "Electric current flow in Amperes (A)." }, "resistance": { "type": "number", "description": "Opposition to current flow in Ohms (\u03a9)." }, "power": { "type": "number", "description": "Rate of energy dissipation in Watts (W)." } }, "description": "Parameters for 'wheel' mode." }, "network_parameters": { "type": "object", "properties": { "source_voltage": { "type": "number", "description": "DC supply voltage in Volts (V)." }, "root_topology": { "type": "string", "enum": [ "series", "parallel" ], "description": "Top-level arrangement of the circuit." }, "elements": { "type": "array", "items": { "type": "object", "properties": { "type": { "type": "string", "enum": [ "resistor", "parallel_group" ] }, "resistance": { "type": "number", "description": "Resistance in Ohms (for individual resistor)." }, "branches": { "type": "array", "items": { "type": "number" }, "description": "Array of parallel branch resistance values in Ohms." } }, "required": [ "type" ] }, "description": "List of circuit elements forming the resistor ladder network." } }, "description": "Parameters for 'resistor_network' mode." }, 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"item": "https://calcworkbench.com/" }, { "@type": "ListItem", "position": 2, "name": "Mathematics & Science Tools", "item": "https://calcworkbench.com/#mathematics" }, { "@type": "ListItem", "position": 3, "name": "Ohm's Law, Power & Resistor Network Calculator", "item": "https://calcworkbench.com/calculators/ohms-law-calculator.html" } ] }, { "@type": "HowTo", "name": "How to Calculate Ohm's Law and Electrical Power (Wheel Formulas)", "description": "Step-by-step procedure to determine unknown voltage, current, resistance, and wattage using the 12 formulas of the Ohm's Law Wheel.", "step": [ { "@type": "HowToStep", "name": "Identify Two Known Electrical Parameters", "text": "Determine any two known electrical values among Voltage (V in Volts), Current (I in Amperes), Resistance (R in Ohms), or Power (P in Watts)." }, { "@type": "HowToStep", "name": "Select the Governing Equation from the 12-Formula Circle Chart", "text": "To find voltage use V = I\u00b7R, V = P/I, or V = \u221a(P\u00b7R). To find current use I = V/R, I = P/V, or I = \u221a(P/R). To find resistance use R = V/I, R = V\u00b2/P, or R = P/I\u00b2. To find power use P = V\u00b7I, P = I\u00b2\u00b7R, or P = V\u00b2/R." }, { "@type": "HowToStep", "name": "Compute the Unknown Quantities", "text": "Substitute the two known inputs into the formula to calculate the remaining two metrics in standard SI engineering units." }, { "@type": "HowToStep", "name": "Verify Continuous Wattage and Component Safety", "text": "Verify that resistors and circuit components are rated to safely dissipate the computed continuous continuous wattage with a 2x safety margin." } ] }, { "@type": "HowTo", "name": "How to Calculate Series, Parallel, and Combination Resistor Networks", "description": "Step-by-step engineering method to calculate equivalent resistance, branch currents, voltage divider drops, and power dissipation in resistor networks.", "step": [ { "@type": "HowToStep", "name": "Identify Circuit Topology", "text": "Identify whether resistors are in series (single continuous path), in parallel (shared common nodes), or a combination ladder network." }, { "@type": "HowToStep", "name": "Compute Equivalent Resistance (Req)", "text": "For series resistors, sum resistances directly: Req = R1 + R2 + ... + Rn. For parallel resistors, sum reciprocals: 1/Req = 1/R1 + 1/R2 + ... + 1/Rn (or Req = (R1\u00b7R2)/(R1+R2) for two branches)." }, { "@type": "HowToStep", "name": "Apply Voltage Divider and Current Divider Rules", "text": "Calculate intermediate voltage drops across series elements using V_drop = V_total \u00b7 (R_target / Req) and branch currents using I_branch = V_node / R_branch." }, { "@type": "HowToStep", "name": "Verify Per-Element Power Dissipation", "text": "Calculate the wattage dissipated in each individual resistor using P_i = I_i\u00b2 \u00b7 R_i to prevent thermal overload." } ] }, { "@type": "HowTo", "name": "How to Calculate the AC and 3-Phase Power Triangle", "description": "Step-by-step procedure to calculate Real Power (P), Reactive Power (Q), Apparent Power (S), and Power Factor (PF) in single-phase and 3-phase AC circuits.", "step": [ { "@type": "HowToStep", "name": "Determine Complex Impedance (Z = R + jX)", "text": "Combine resistance (R) with net reactance (X = XL - XC) to find total impedance magnitude |Z| = \u221a(R\u00b2 + X\u00b2) and phase angle \u03b8 = arctan(X/R)." }, { "@type": "HowToStep", "name": "Calculate Apparent Power (S)", "text": "For single-phase, S = V_rms \u00b7 I_rms. For balanced 3-phase systems, S_3ph = \u221a3 \u00b7 V_LL \u00b7 I_L." }, { "@type": "HowToStep", "name": "Derive Real Power (P) and Reactive Power (Q)", "text": "Calculate working Real Power P = S \u00b7 cos(\u03b8) in Watts and Reactive Power Q = S \u00b7 sin(\u03b8) in VAR, satisfying the Pythagorean identity S\u00b2 = P\u00b2 + Q\u00b2." }, { "@type": "HowToStep", "name": "Size Power Factor Correction Capacitors", "text": "Determine required corrective reactive power Qc = P \u00b7 (tan(\u03b81) - tan(\u03b82)) and calculate parallel capacitance C = Qc / (2\u03c0 \u00b7 f \u00b7 V\u00b2)." } ] }, { "@type": "FAQPage", "@id": "https://calcworkbench.com/calculators/ohms-law-calculator.html#faq", "mainEntity": [ { "@type": "Question", "name": "What is Ohm's Law and how do you calculate it?", "acceptedAnswer": { "@type": "Answer", "text": "Ohm's Law states that the current flowing through an electrical conductor between two points is directly proportional to the voltage and inversely proportional to the resistance: V = I \u00b7 R. To calculate voltage, multiply current by resistance (V = I \u00b7 R); to calculate current, divide voltage by resistance (I = V / R); and to calculate resistance, divide voltage by current (R = V / I)." } }, { "@type": "Question", "name": "How do you calculate power and find watts using Ohm's Law?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate electrical power in Watts using Ohm's Law and Joule's Law, multiply voltage by current (P = V \u00b7 I), or substitute known resistance to use P = I\u00b2 \u00b7 R or P = V\u00b2 / R. These formulas allow you to find watts immediately whenever any two circuit metrics are known." } }, { "@type": "Question", "name": "How do you find amps, voltage, and resistance using Ohm's Law?", "acceptedAnswer": { "@type": "Answer", "text": "To find amps (current), divide voltage by resistance (I = V / R) or power by voltage (I = P / V); to find voltage, multiply amps by resistance (V = I \u00b7 R) or divide power by amps (V = P / I); and to find resistance, divide voltage by amps (R = V / I) or square voltage divided by watts (R = V\u00b2 / P)." } }, { "@type": "Question", "name": "What are the 12 formulas of the Ohm's Law Wheel (circle chart / pie chart / diagram)?", "acceptedAnswer": { "@type": "Answer", "text": "The 12 formulas of the Ohm's Law Wheel chart calculate every combination of Voltage (V), Current (I), Resistance (R), and Power (P): For Voltage: V = I\u00b7R, V = P/I, V = \u221a(P\u00b7R). For Current: I = V/R, I = P/V, I = \u221a(P/R). For Resistance: R = V/I, R = V\u00b2/P, R = P/I\u00b2. For Power: P = V\u00b7I, P = I\u00b2\u00b7R, P = V\u00b2/R." } }, { "@type": "Question", "name": "How does an Ohm's Law DC calculator differ from an AC calculator?", "acceptedAnswer": { "@type": "Answer", "text": "An Ohm's Law DC calculator assumes purely resistive steady-state conduction where voltage and current are in phase and power factor equals 1.0 (P = V\u00b7I). In AC circuits, frequency-dependent inductive and capacitive reactances create complex impedance Z = R + jX and phase shifts, requiring the AC power triangle to distinguish between Real Power (Watts), Reactive Power (VAR), and Apparent Power (VA)." } }, { "@type": "Question", "name": "How do you calculate Ohm's Law in a 3-phase circuit?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate electrical values in a balanced 3-phase AC circuit, multiply line-to-line voltage by line current, the square root of 3 (approximately 1.732), and the power factor: Apparent Power S = \u221a3 \u00b7 V_LL \u00b7 I_L, and Real Power P = \u221a3 \u00b7 V_LL \u00b7 I_L \u00b7 PF. For equivalent phase impedance in wye loads, phase voltage equals line voltage divided by \u221a3." } }, { "@type": "Question", "name": "How do you calculate speaker impedance and audio amplifier wattage using Ohm's Law?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate speaker impedance and amplifier wattage, use the power formula P = V\u00b2 / R. For example, an amplifier delivering 20 VRMS into an 8-Ohm speaker produces P = (20)\u00b2 / 8 = 50 Watts RMS. When wiring multiple speakers, two 8-Ohm speakers in parallel produce a 4-Ohm equivalent load, drawing double the current from the amplifier." } }, { "@type": "Question", "name": "How do you calculate the resistor needed for an LED circuit?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate the current-limiting resistor needed for an LED, subtract the forward voltage drop of the LED from the power supply voltage and divide by the desired forward current: R = (V_source - V_forward) / I_desired. For example, connecting a 2V red LED to a 9V battery at 20mA (0.02A) requires R = (9 - 2) / 0.02 = 350 Ohms, dissipating P = (0.02)\u00b2 \u00b7 350 = 0.14 Watts." } }, { "@type": "Question", "name": "How do you calculate Ohm's Law in a series circuit?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate Ohm's Law in a series circuit, sum all individual resistances to find equivalent resistance (Req = R1 + R2 + ... + Rn) because electrical current remains identical through every series component. The circuit current is I = V_total / Req, and the voltage drop across each individual resistor equals V_i = I \u00b7 R_i per Kirchhoff's Voltage Law." } }, { "@type": "Question", "name": "How do you calculate Ohm's Law in a parallel circuit?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate Ohm's Law in a parallel circuit, apply the constant source voltage across each branch and sum reciprocal resistances to find equivalent resistance: 1/Req = 1/R1 + 1/R2 + ... + 1/Rn. Branch currents divide inversely to resistance (I_i = V / R_i), and total supply current is the sum of all branch currents per Kirchhoff's Current Law." } }, { "@type": "Question", "name": "Why is parallel resistance always less than the smallest branch resistor?", "acceptedAnswer": { "@type": "Answer", "text": "Equivalent resistance in a parallel circuit is always less than the smallest resistor because each additional branch adds an extra physical pathway for charge carriers to flow, increasing total conductance (G = 1/R). Greater total conductance means less total opposition to current flow, making total equivalent resistance lower than any single branch alone." } }, { "@type": "Question", "name": "How does a resistor network voltage divider calculator work?", "acceptedAnswer": { "@type": "Answer", "text": "A resistor network voltage divider calculates the output potential across a lower branch resistor using the ratio V_out = V_in \u00b7 (R2 / (R1 + R2)). This linear proportion splits input voltage without active semiconductor components, provided the downstream load impedance is significantly larger than R2 to avoid loading error." } }, { "@type": "Question", "name": "How do you calculate combination circuits and resistor ladder networks?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate resistor ladder networks and combination circuits with multiple resistors, solve the circuit step-by-step from the farthest branch backward toward the power source by alternating between series sums and parallel reductions. Once the single equivalent input resistance is established, solve total current and step forward to derive node voltages and individual resistor power dissipations." } }, { "@type": "Question", "name": "What are Pi (\u03c0) and Tee (T) resistive matching attenuator networks?", "acceptedAnswer": { "@type": "Answer", "text": "Pi (\u03c0) and Tee (T) resistor networks are three-element symmetric or asymmetric resistor arrays designed to attenuate signal amplitude while matching input and output characteristic impedances (such as 50 \u03a9 or 75 \u03a9 RF lines). A Pi network configures two parallel shunt resistors around a central series resistor, while a T network configures two series resistors with a central parallel shunt to ground." } }, { "@type": "Question", "name": "What is the formula for calculating the AC Power Triangle?", "acceptedAnswer": { "@type": "Answer", "text": "The fundamental formula for calculating the AC power triangle is the right-triangle Pythagorean relation S\u00b2 = P\u00b2 + Q\u00b2, where S is Apparent Power in Volt-Amperes (VA), P is Real Power in Watts (W), and Q is Reactive Power in Volt-Amperes Reactive (VAR). The power factor angle satisfies cos(\u03b8) = P / S and tan(\u03b8) = Q / P." } }, { "@type": "Question", "name": "What is the difference between Real Power, Reactive Power, and Apparent Power?", "acceptedAnswer": { "@type": "Answer", "text": "Real Power (P in Watts) performs actual physical work such as producing mechanical torque or thermal heat; Reactive Power (Q in VAR) cyclically sustains magnetic and electric fields in inductors and capacitors without performing net work; and Apparent Power (S in VA) is the total vector magnitude supplied by the utility (S = V_rms \u00b7 I_rms)." } }, { "@type": "Question", "name": "What does 'j' represent in complex impedance Z = R + jX?", "acceptedAnswer": { "@type": "Answer", "text": "In electrical engineering, 'j' represents the imaginary unit \u221a(\u22121), used instead of 'i' to avoid confusion with electric current. It indicates a 90-degree spatial phase shift: pure resistance (R) dissipates energy in-phase with current, while reactance (jX) stores energy in magnetic (+jXL for inductors) or electric (\u2212jXC for capacitors) fields 90 degrees out-of-phase." } }, { "@type": "Question", "name": "How do you calculate power factor correction capacitance?", "acceptedAnswer": { "@type": "Answer", "text": "To calculate the power factor correction capacitor needed to improve an inductive load from an initial power factor angle \u03b81 to target \u03b82, compute required corrective VARs via Qc = P \u00b7 (tan(\u03b81) - tan(\u03b82)) and solve capacitance via C = Qc / (2\u03c0 \u00b7 f \u00b7 V_rms\u00b2). Installing shunt capacitors supplies reactive power locally, lowering total utility current draw and eliminating low-power-factor billing surcharges." } } ] } ] } ```