Solve any equation forward or backward—click any variable to make it the target with automatic SI unit conversions.
Solve Re = (ρ × v × D) / μ for dimensionless Reynolds number, fluid density, pipe velocity, hydraulic diameter, or dynamic viscosity.
Solve the incompressible continuity equation Q = A × v for volumetric flow rate, cross-sectional pipe area, or fluid velocity.
Solve h_f = f × (L / D) × (v² / 2g) for frictional head loss in meters, Darcy friction factor, pipe length, internal diameter, or flow velocity.
Solve ΔP = 0.5 × ρ × (v₂² - v₁²) for Venturi static pressure drop, fluid density, upstream velocity, or throat velocity.
Solve δ = (F × L³) / (3 × E × I) for maximum tip deflection, point load F, beam span L, Young's modulus E, or area moment of inertia I.
Solve σ = (F × L) / (4 × S) for peak midspan flexural bending stress, center point load, span length, or elastic section modulus.
Solve C = ε_r × ε₀ × A / d for capacitance in picofarads (pF), dielectric constant, plate overlap area, or dielectric separation.
Solve f_c = 1 / (2πRC) for -3 dB filter cutoff frequency, series resistance R, or filter capacitance C.
Solve X_L = 2πfL for AC inductive reactance in Ohms, operating frequency in Hertz, or inductance in millihenries.
Solve f₀ = 1 / (2π√(LC)) for natural LC resonant frequency, tank inductance L, or tuning capacitance C.
Solve V_s / V_p = N_s / N_p for secondary output voltage, primary input voltage, primary winding turns, or secondary winding turns.
Solve P = √3 × V_L × I_L × PF for three-phase real power in Watts/kW, line-to-line voltage, line current, or power factor.
Solve V_out = V_in × R₂ / (R₁ + R₂) for output tap voltage, supply voltage, top series resistor R₁, or bottom shunt resistor R₂.
Solve R = (V_s - V_f) / I_f for current-limiting resistor value, supply voltage, LED forward voltage drop, or forward current.
Solve η_max = (1 - T_C / T_H) × 100 for theoretical maximum thermal efficiency, hot reservoir temperature, or cold sink temperature in Kelvin.
Solve COP = Q_thermal / W_elec for refrigeration or heat-pump Coefficient of Performance, thermal cooling/heating capacity, or compressor electrical power.
Solve P_shaft = (ρ × g × Q × H) / η for pump shaft power, volumetric flow rate, total dynamic head, fluid density, or pump efficiency.
Solve T_out = T_in × (N_out / N_in) × η for output shaft torque, input motor torque, driven gear teeth, driver pinion teeth, or transmission efficiency.
Solve T = K × F × d for fastener installation torque, axial clamp preload force, nut factor K, or nominal bolt diameter.
Solve ΔL = (F × L₀) / (A × E) for axial elastic elongation, tensile/compressive load, original bar length, cross-sectional area, or Young's modulus.