What is the formula for density?

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What is the formula for density​?

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Basic Density FormulasFormula TypeFormulaVariablesUnitsApplicationMass Densityρ = m/Vρ = density, m = mass, V = volumekg/m³, g/cm³General physics, material scienceLinear Densityλ = m/Lλ = linear density, m = mass, L = lengthkg/m, g/cmStrings, wires, rodsSurface Densityσ = m/Aσ = surface density, m = mass, A = areakg/m², g/cm²Thin sheets, membranesNumber Densityn = N/Vn = number density, N = number of particles, V = volumeparticles/m³Particle physics, gas dynamicsRelative and Specific Density Formula TypeFormulaVariablesUnitsApplicationRelative DensityRD = ρ_substance/ρ_waterRD = relative density, ρ_substance = density of substance, ρ_water = density of waterDimensionlessComparing densities to waterSpecific GravitySG = ρ_substance/ρ_referenceSG = specific gravity, ρ_reference = reference fluid densityDimensionlessEngineering, geologyBulk Densityρ_bulk = m_total/V_totalρ_bulk = bulk density, m_total = total mass, V_total = total volumekg/m³Powders, granular materialsApparent Densityρ_app = m_dry/V_bulkρ_app = apparent density, m_dry = dry mass, V_bulk = bulk volumekg/m³Porous materialsCurrent Density Formula TypeFormulaVariablesUnitsApplicationCurrent DensityJ = I/AJ = current density, I = current, A = cross-sectional areaA/m²Electrical engineeringCurrent Density (Microscopic)J = nqvJ = current density, n = charge carrier density, q = charge, v = drift velocityA/m²Semiconductor physicsDrift Current DensityJ_drift = σEJ_drift = drift current density, σ = conductivity, E = electric fieldA/m²Electronic devicesDiffusion Current DensityJ_diff = qD(dn/dx)J_diff = diffusion current, q = charge, D = diffusion coefficient, dn/dx = concentration gradientA/m²Semiconductor junctionsEnergy Density {#energy-density}Formula TypeFormulaVariablesUnitsApplicationEnergy Densityu = E/Vu = energy density, E = energy, V = volumeJ/m³General energy calculationsElectric Field Energy Densityu_E = (1/2)ε₀E²u_E = electric energy density, ε₀ = permittivity of free space, E = electric fieldJ/m³Capacitors, electromagnetic fieldsMagnetic Field Energy Densityu_B = B²/(2μ₀)u_B = magnetic energy density, B = magnetic field, μ₀ = permeability of free spaceJ/m³Inductors, magnetic fieldsElectromagnetic Energy Densityu_EM = u_E + u_Bu_EM = total electromagnetic energy densityJ/m³Electromagnetic wavesGravitational Energy Densityu_g = (1/2)ρghu_g = gravitational energy density, ρ = density, g = acceleration due to gravity, h = heightJ/m³Gravitational fieldsMagnetic Flux Density {#magnetic-flux-density}Formula TypeFormulaVariablesUnitsApplicationMagnetic Flux DensityB = Φ/AB = magnetic flux density, Φ = magnetic flux, A = areaTesla (T), Weber/m²Magnetic field calculationsMagnetic Field StrengthB = μHB = magnetic flux density, μ = permeability, H = magnetic field intensityTMagnetic materialsForce on Current Carrying WireF = BIL sin θF = force, B = magnetic flux density, I = current, L = length, θ = angleNElectric motors, generatorsLorentz ForceF = q(v × B)F = force, q = charge, v = velocity, B = magnetic flux densityNParticle acceleratorsVapour Density {#vapour-density}Formula TypeFormulaVariablesUnitsApplicationVapour DensityVD = M/(2 × 2) = M/4VD = vapour density, M = molecular massDimensionlessChemistry, molecular mass determinationVapour Density (Relative)VD = ρ_vapour/ρ_H₂VD = vapour density, ρ_vapour = density of vapour, ρ_H₂ = density of hydrogenDimensionlessGas analysisMolecular Mass from VDM = 2 × VDM = molecular mass, VD = vapour densityg/molMolecular weight determinationVapour Density (STP)VD = (22.4 × ρ)/(M)ρ = density at STP, M = molecular massDimensionlessStandard conditionsPopulation and Area Density {#population-density}Formula TypeFormulaVariablesUnitsApplicationPopulation DensityPD = P/APD = population density, P = population, A = areapeople/km², people/mi²Demographics, urban planningPacking Densityη = V_occupied/V_totalη = packing efficiency, V_occupied = occupied volume, V_total = total volumeDimensionlessCrystal structuresAtomic Packing FactorAPF = (N × V_atom)/V_unit cellAPF = atomic packing factor, N = atoms per unit cell, V_atom = atomic volumeDimensionlessMaterials scienceCharge Densityρ_q = Q/Vρ_q = charge density, Q = total charge, V = volumeC/m³ElectrostaticsProbability Density {#probability-density}Formula TypeFormulaVariablesUnitsApplicationProbability Density Functionf(x) = dP/dxf(x) = probability density function, P = probability, x = variableVariesStatistics, quantum mechanicsNormal Distributionf(x) = (1/σ√2π)e^(-(x-μ)²/2σ²)μ = mean, σ = standard deviation, x = variableVariesStatisticsWave Function Probabilityψ²(x) = |ψ(x)|²ψ = wave function, x = positionm⁻³Quantum mechanicsRadial Probability DensityP(r) = 4πr²ψ²(r)P(r) = radial probability, r = radius, ψ = wave functionm⁻¹Atomic orbitalsDimensional Analysis {#dimensional-analysis}QuantityDimensional FormulaSI Base UnitsExplanationMass Density[M L⁻³]kg⋅m⁻³Mass per unit volumeCurrent Density[A L⁻²]A⋅m⁻²Current per unit areaEnergy Density[M L⁻¹ T⁻²]kg⋅m⁻¹⋅s⁻²Energy per unit volumeMagnetic Flux Density[M T⁻² A⁻¹]kg⋅s⁻²⋅A⁻¹Magnetic field strengthCharge Density[A T L⁻³]A⋅s⋅m⁻³Charge per unit volumeLinear Density[M L⁻¹]kg⋅m⁻¹Mass per unit lengthSurface Density[M L⁻²]kg⋅m⁻²Mass per unit area

What is the formula for density?

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Formula Type	Formula	Variables	Units	Application
Mass Density	ρ = m/V	ρ = density, m = mass, V = volume	kg/m³, g/cm³	General physics, material science
Linear Density	λ = m/L	λ = linear density, m = mass, L = length	kg/m, g/cm	Strings, wires, rods
Surface Density	σ = m/A	σ = surface density, m = mass, A = area	kg/m², g/cm²	Thin sheets, membranes
Number Density	n = N/V	n = number density, N = number of particles, V = volume	particles/m³	Particle physics, gas dynamics

Quantity	Dimensional Formula	SI Base Units	Explanation
Mass Density	[M L⁻³]	kg⋅m⁻³	Mass per unit volume
Current Density	[A L⁻²]	A⋅m⁻²	Current per unit area
Energy Density	[M L⁻¹ T⁻²]	kg⋅m⁻¹⋅s⁻²	Energy per unit volume
Magnetic Flux Density	[M T⁻² A⁻¹]	kg⋅s⁻²⋅A⁻¹	Magnetic field strength
Charge Density	[A T L⁻³]	A⋅s⋅m⁻³	Charge per unit volume
Linear Density	[M L⁻¹]	kg⋅m⁻¹	Mass per unit length
Surface Density	[M L⁻²]	kg⋅m⁻²	Mass per unit area

Formula Type	Formula	Variables	Units	Application
Probability Density Function	f(x) = dP/dx	f(x) = probability density function, P = probability, x = variable	Varies	Statistics, quantum mechanics
Normal Distribution	f(x) = (1/σ√2π)e^(-(x-μ)²/2σ²)	μ = mean, σ = standard deviation, x = variable	Varies	Statistics
Wave Function Probability	ψ²(x) = \|ψ(x)\|²	ψ = wave function, x = position	m⁻³	Quantum mechanics
Radial Probability Density	P(r) = 4πr²ψ²(r)	P(r) = radial probability, r = radius, ψ = wave function	m⁻¹	Atomic orbitals

What is the formula for density​?

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What is the formula for density?