What is Ohm's law as a formula? What is ohm's law formula in physics?

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Complete Guide to Ohm's Law FormulasOhm's Law is one of the fundamental principles in electrical engineering and physics, discovered by German physicist Georg Simon Ohm in 1827. It describes the relationship between voltage, current, and resistance in an electrical circuit.The Basic Ohm's Law FormulaV = I × RWhere:V = Voltage (measured in Volts, V)I = Current (measured in Amperes, A)R = Resistance (measured in Ohms, Ω)Complete Ohm's Law Formula TableFormulaSymbol RepresentationPurposeWhen to UseVoltage FormulaV = I × RCalculate voltage when current and resistance are knownWhen you need to find potential difference across a componentCurrent FormulaI = V ÷ RCalculate current when voltage and resistance are knownWhen determining how much current flows through a circuitResistance FormulaR = V ÷ ICalculate resistance when voltage and current are knownWhen finding the opposition to current flow in a circuitOhm's Law TriangleThe Ohm's Law Triangle is a visual memory aid that helps students remember the three formulas: V
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 I RHow to Use the Triangle:Cover the variable you want to findThe remaining two variables show the formulaIf they're side by side: multiply themIf one is on top: divide top by bottomExamples:Cover V → V = I × RCover I → I = V ÷ RCover R → R = V ÷ IDetailed Formula Breakdown1. Voltage (Potential Difference) FormulasFormulaDescriptionUnitExampleV = I × RBasic voltage calculationVolts (V)If I = 2A and R = 10Ω, then V = 20VV = P ÷ IVoltage using power and currentVolts (V)If P = 100W and I = 5A, then V = 20VV = √(P × R)Voltage using power and resistanceVolts (V)If P = 100W and R = 4Ω, then V = 20V2. Current (Amperage) FormulasFormulaDescriptionUnitExampleI = V ÷ RBasic current calculationAmperes (A)If V = 12V and R = 6Ω, then I = 2AI = P ÷ VCurrent using power and voltageAmperes (A)If P = 60W and V = 12V, then I = 5AI = √(P ÷ R)Current using power and resistanceAmperes (A)If P = 100W and R = 25Ω, then I = 2A3. Resistance FormulasFormulaDescriptionUnitExampleR = V ÷ IBasic resistance calculationOhms (Ω)If V = 24V and I = 3A, then R = 8ΩR = P ÷ I²Resistance using power and currentOhms (Ω)If P = 100W and I = 5A, then R = 4ΩR = V² ÷ PResistance using voltage and powerOhms (Ω)If V = 20V and P = 100W, then R = 4ΩPower Formulas Related to Ohm's LawFormulaDescriptionWhen to UseP = V × IPower using voltage and currentWhen both V and I are knownP = I² × RPower using current and resistanceWhen I and R are knownP = V² ÷ RPower using voltage and resistanceWhen V and R are knownWhere P = Power (measured in Watts, W)Practical ApplicationsSeries Circuit FormulasParameterFormulaNotesTotal ResistanceR_total = R₁ + R₂ + R₃ + ...Resistances add upCurrentI_total = I₁ = I₂ = I₃Same current throughoutTotal VoltageV_total = V₁ + V₂ + V₃ + ...Voltages add upParallel Circuit FormulasParameterFormulaNotesTotal Resistance1/R_total = 1/R₁ + 1/R₂ + 1/R₃ + ...Reciprocal formulaTotal CurrentI_total = I₁ + I₂ + I₃ + ...Currents add upVoltageV_total = V₁ = V₂ = V₃Same voltage across all branchesQuick Reference: Ohm's Law WheelAll 12 formulas derived from Ohm's Law and Power Law:To FindKnown ValuesFormulaVoltage (V)I and RV = I × RVoltage (V)P and IV = P ÷ IVoltage (V)P and RV = √(P × R)Current (I)V and RI = V ÷ RCurrent (I)P and VI = P ÷ VCurrent (I)P and RI = √(P ÷ R)Resistance (R)V and IR = V ÷ IResistance (R)P and IR = P ÷ I²Resistance (R)V and PR = V² ÷ PPower (P)V and IP = V × IPower (P)I and RP = I² × RPower (P)V and RP = V² ÷ RImportant Points to RememberOhm's Law applies only to ohmic conductors - materials where resistance remains constant regardless of voltage or currentLinear relationship - The relationship between voltage and current is linear in ohmic materialsTemperature effects - Resistance can change with temperature, affecting calculationsSI Units are essential - Always use Volts, Amperes, and Ohms for accurate calculationsCircuit type matters - Series and parallel circuits have different rules for calculating total resistancePractice ProblemsProblem 1: Finding VoltageGiven: Current (I) = 3A, Resistance (R) = 15ΩFormula: V = I × RSolution: V = 3 × 15 = 45VProblem 2: Finding CurrentGiven: Voltage (V) = 230V, Resistance (R) = 46ΩFormula: I = V ÷ RSolution: I = 230 ÷ 46 = 5AProblem 3: Finding ResistanceGiven: Voltage (V) = 12V, Current (I) = 0.5AFormula: R = V ÷ ISolution: R = 12 ÷ 0.5 = 24Ω

What is Ohm's law as a formula? What is ohm's law formula in physics?

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Formula	Symbol Representation	Purpose	When to Use
Voltage Formula	V = I × R	Calculate voltage when current and resistance are known	When you need to find potential difference across a component
Current Formula	I = V ÷ R	Calculate current when voltage and resistance are known	When determining how much current flows through a circuit
Resistance Formula	R = V ÷ I	Calculate resistance when voltage and current are known	When finding the opposition to current flow in a circuit

Formula	Description	Unit	Example
V = I × R	Basic voltage calculation	Volts (V)	If I = 2A and R = 10Ω, then V = 20V
V = P ÷ I	Voltage using power and current	Volts (V)	If P = 100W and I = 5A, then V = 20V
V = √(P × R)	Voltage using power and resistance	Volts (V)	If P = 100W and R = 4Ω, then V = 20V

Formula	Description	When to Use
P = V × I	Power using voltage and current	When both V and I are known
P = I² × R	Power using current and resistance	When I and R are known
P = V² ÷ R	Power using voltage and resistance	When V and R are known

Parameter	Formula	Notes
Total Resistance	R_total = R₁ + R₂ + R₃ + ...	Resistances add up
Current	I_total = I₁ = I₂ = I₃	Same current throughout
Total Voltage	V_total = V₁ + V₂ + V₃ + ...	Voltages add up

To Find	Known Values	Formula
Voltage (V)	I and R	V = I × R
Voltage (V)	P and I	V = P ÷ I
Voltage (V)	P and R	V = √(P × R)
Current (I)	V and R	I = V ÷ R
Current (I)	P and V	I = P ÷ V
Current (I)	P and R	I = √(P ÷ R)
Resistance (R)	V and I	R = V ÷ I
Resistance (R)	P and I	R = P ÷ I²
Resistance (R)	V and P	R = V² ÷ P
Power (P)	V and I	P = V × I
Power (P)	I and R	P = I² × R
Power (P)	V and R	P = V² ÷ R