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1822 apps · Showing 1249–1344

Data & Calculators: Physics Calculators

Cell EMF, Terminal Voltage & Internal Resistance

Relate a cell’s ideal EMF, internal resistance and a positive resistive load during discharge.

Centrifuge RPM & Relative Force from Rotor Radius

Convert between RPM and relative centrifugal force using the entered rotor radius and the conventional rounded coefficient.

Charge Magnitude to Equivalent Excess Electrons

Convert a nonnegative charge magnitude to an equivalent electron count with eight charge units, sixty count scales and the exact elementary-charge default.

Charge, Voltage & Electric Potential Energy

Convert charge and electric potential difference into signed potential-energy change, in electron-volts or joules.

Charged Particle Acceleration in an Electric Field

Calculate charged particle acceleration in an electric field with compatible units, known-value inputs and clearly stated model assumptions.

Circuit Resistance and Material Resistivity from Ohmic Fields

Recover component resistance from positive circuit measurements, and separately recover material resistivity from electric field and current density, with preserved inverse controls.

Circular Aperture Rayleigh Resolution

Estimate the small-angle diffraction limit from wavelength and an ideal circular aperture diameter.

Circular Motion: Period, Speed & Inward Acceleration

Relate period, cycle frequency and angular rate, or add radius to calculate tangential speed and centripetal acceleration.

Circular Shaft Twist from Torque & Torsional Rigidity

Calculate elastic twist of a uniform circular shaft using torque, length, polar second moment of area and shear modulus, including reverse inputs.

Circular-Motion Force, Acceleration & Angular Speed

Solve circular-motion relationships for force, acceleration, speed, radius or mass, with angular-speed unit conversion.

Classical Kinetic Energy from Mass & Speed

Calculate translational kinetic energy, mass or the nonnegative speed corresponding to an entered energy.

Classical Mobility, Diffusion and Carrier Charge

Relate diffusion coefficient, electrical mobility, absolute temperature and positive carrier-charge magnitude using the classical Einstein relation and exact SI Boltzmann constant.

Closed-Surface Electric Flux from Enclosed Charge

Relate positive enclosed charge, total electric flux and the permittivity parameter, retaining charge units, two flux units and an editable locked vacuum default.

Compression Bulk Modulus & Volume Strain

Calculate positive bulk modulus from a pressure increase and a negative volume change, retaining signed compressive strain.

Compton Photon Scattering Wavelength Shift

Calculate compton photon scattering wavelength shift with compatible units, known-value inputs and clearly stated model assumptions.

Conical Heap Slope Angle, Height & Radius

Relate height and radius of an ideal conical heap to slope angle and a simple friction-equivalent ratio.

Constant-Pressure Gas Volume, Temperature and Amount

Relate two positive ideal-gas states with fixed pressure and amount, preserve editable units and inverse controls, and calculate optional amount through the initial state.

Constant-Temperature Gas Pressure, Volume and Amount

Relate absolute pressures and volumes at fixed temperature, preserve unit and inverse controls, and calculate the read-only amount from the initial state.

Cooling Capacity: BTU/h, Watts and Refrigeration Tons

Convert positive heat-removal capacity between International Table BTUs per hour, watts with metric prefixes, and refrigeration tons using exact unit relationships.

Critical Damping & Natural Frequency

Find critical viscous damping, mass, stiffness and the undamped natural frequency of a linear spring–mass system.

Cube Mass, Density, Volume and Diagonal Measurements

Relate a positive cube mass and density to its volume, edge, face diagonal and space diagonal while retaining every unit selector.

Cylinder Mass, Density, Radius & Height

Solve density and mass from volume, or reveal cylinder dimensions to calculate volume from radius and height.

DC Voltage–Current Power & Resistance Ratio

Calculate signed DC power and the voltage-to-current ratio at a nonzero operating point.

Decibel Gain from Power or Voltage Ratios

Convert positive power ratios and positive voltage-magnitude ratios to independent decibel gains.

Density from Mass & Rectangular Dimensions

Find density from positive mass and volume, or derive a rectangular solid’s volume from its three dimensions, with reverse calculations and unit choices.

Density from Volume & Known Mass

Find density from positive mass and volume, or derive a rectangular solid’s volume from its three dimensions, with reverse calculations and unit choices.

Density, Mass, Volume & Box Dimensions

Solve average density, mass or volume, with optional length, width and height for a rectangular solid.

Dielectric Brewster Angle & Index Ratio

Calculate Brewster angle or either positive refractive index for an ideal dielectric interface.

Displaced Fluid, Buoyant Force & Mass

Solve buoyant force, displaced fluid mass or displaced volume using fluid density and local gravity.

Drag-Based Ballistic Mass to Area

Find the drag-based mass-to-area coefficient, or solve for mass, reference area or drag coefficient using consistent SI or customary units.

Drivetrain Crawl Ratio & Gear Tooth Ratio

Multiply transmission, transfer-case and axle ratios, and calculate a separate axle ratio from ring and pinion tooth counts.

Dynamic & Kinematic Viscosity with Density

Convert between positive dynamic and kinematic viscosity using mass density at the same fluid conditions.

Elastic Solid Shear Wave Speed

Relate shear modulus, density and shear wave speed in a homogeneous linear elastic solid.

Electrical Conductivity & Resistivity Converter

Convert electrical conductivity and resistivity in either direction, with selectable material examples and custom values.

Energy Transition Gap and Photon Frequency

Convert an energy-level gap to photon frequency, or recover either signed energy level, using exact Planck conversion and independent energy units.

Energy-Based Capacitance, Voltage and Stored Energy

Solve ideal capacitance, voltage magnitude or stored electrical energy with editable results, joule and watt-hour units, and farad prefixes.

Engine Bore, Stroke & Swept Volume

Find total swept displacement from a common cylinder bore, stroke and positive whole-cylinder count.

Engine Torque, Displacement & BMEP

Calculate brake mean effective pressure from torque, total swept displacement and crankshaft revolutions per cycle.

Engineering Length Strain & Entered Threshold Comparison

Calculate engineering strain from original and final length and compare it with an explicitly illustrative or custom threshold.

F-Number, Entrance Pupil Diameter & Area

Relate focal length, f-number and the diameter and area of an ideal circular entrance pupil.

Fan Airflow, Pressure Rise and DC Input Power

Balance fan air power, volumetric flow per minute and pressure rise with DC voltage, current and overall efficiency; solve any unknown using selectable units.

First-Order RC & RL Corner Frequency

Find the ideal first-order corner frequency for a selected RC or RL circuit model.

Flash-to-Thunder Delay and Distance Estimate

Estimate lightning sound-path distance from the measured flash-to-thunder delay and an editable positive sound speed.

Fluid Depth & Hydrostatic Absolute Pressure

Calculate absolute pressure at depth from fluid density, gravity and surface pressure, with reverse solutions and density presets.

Fluid Drag Force, Coefficient & Area

Calculate positive drag force from fluid density, relative speed, drag coefficient and its matching reference area.

Force, Radius & Angle Torque Magnitude

Calculate the magnitude of a single force’s torque about a pivot, including its direction angle.

Four-Stroke Engine Airflow Demand

Estimate four-stroke engine airflow from displacement, RPM and volumetric efficiency, or recover a missing quantity in SI and customary units.

Free-Fall Arrival Velocity, Drop Distance & Time

Solve the downward displacement, elapsed time and initial velocity of an ideal fall under constant gravity, preserving reverse inputs and unit choices.

Free-Fall Distance from Time, Initial Speed & Gravity

Solve the downward displacement, elapsed time and initial velocity of an ideal fall under constant gravity, preserving reverse inputs and unit choices.

Free-Fall Height & Time with Initial Velocity

Solve the downward displacement, elapsed time and initial velocity of an ideal fall under constant gravity, preserving reverse inputs and unit choices.

Free-Fall Time from Drop Distance & Initial Velocity

Solve the downward displacement, elapsed time and initial velocity of an ideal fall under constant gravity, preserving reverse inputs and unit choices.

Frequency from Wavelength & Wave Speed

Convert between wavelength and frequency using a medium preset or your own positive phase speed.

Frequency Prefix Conversion in Hertz

Calculate frequency prefix conversion in hertz with compatible units, known-value inputs and clearly stated model assumptions.

Friction Coefficient & Normal Force

Calculate μN for kinetic friction or a maximum static-friction estimate using a supplied coefficient.

Friction Force from Contact Load & Coefficient

Find kinetic friction or the limiting static friction from a coefficient and the normal contact force.

Friction, Normal Force & Coefficient

Relate sliding friction or limiting static friction to normal force and a nonnegative friction coefficient.

Full Circular Pipe Flow & Mean Velocity

Relate volumetric flow rate, inside pipe diameter and cross-sectional mean speed for a full circular pipe.

Gas Compressibility Factor and Missing State Values

Calculate positive compressibility factor from measured gas-state quantities, or recover a supported missing quantity with a known positive factor.

Gas Volume & Amount at Constant Temperature and Pressure

Use Avogadro’s relation to calculate one gas volume or amount from the other three positive values.

Gear Speed Reduction & Reciprocal Multiplier

Find the tooth ratio, output speed and reciprocal speed multiplier for a compatible gear pair.

Gear Teeth Ratio & Output RPM

Calculate a gear ratio from tooth counts and convert between input and output rotation rates.

Gear Tooth Count, Pitch Diameter & Module

Relate positive whole tooth count, pitch-circle diameter, tooth density and gear module.

Grams & Cubic Centimeters by Density

Convert between mass in grams and volume in cubic centimeters using the density you supply.

Gravitational Potential Energy from Reference Height

Relate mass and signed height to gravitational potential energy in a uniform gravitational field.

Gravity from Mass & Center Distance

Relate gravitational acceleration, source mass and distance from its center using Newton’s inverse-square model.

Horizontal Coriolis Force, Acceleration and Signed Latitude

Evaluate a signed horizontal Coriolis scalar for a moving mass, with editable frame rotation, latitude, acceleration, unit selectors and supported inverses.

Hubble Rate, Distance and Cosmic Recession Speed

Relate an assumed Hubble rate, positive proper distance and cosmic recession speed, with signed rates, zero-case handling and independent speed/distance units.

Hydraulic Head Difference & Gradient

Find the signed head drop per unit distance between two points sharing a hydraulic-head datum.

Ideal Boost Converter Duty Cycle and Ripple Inductance

Calculate ideal boost converter duty cycle and ripple inductance using known measurements, selectable units and clear physical assumptions.

Ideal Broad-Crested Weir Head, Width & Flow

Estimate ideal rectangular broad-crested weir discharge from upstream head, transverse crest width and gravity.

Ideal Buck Converter Duty Cycle and Ripple Inductance

Calculate ideal buck converter duty cycle and ripple inductance using known measurements, selectable units and clear physical assumptions.

Ideal Gas Molecular Root Mean Square Speed

Find molecular RMS speed from absolute temperature and molar mass, with retained gas presets, custom mass and reviewed hydrogen and water values.

Ideal Gas Pressure from State & Moles

Find ideal-gas pressure from the pressure-volume-temperature relation, with optional gas mass and molar mass to determine moles.

Ideal Gas Pressure, Volume, Amount and Gas Mass

Calculate ideal gas pressure, volume, amount and gas mass using known measurements, selectable units and clear physical assumptions.

Ideal Gas Temperature from State & Moles

Find ideal-gas temperature from the pressure-volume-temperature relation, with optional gas mass and molar mass to determine moles.

Ideal Gas Volume from State & Moles

Find ideal-gas volume from the pressure-volume-temperature relation, with optional gas mass and molar mass to determine moles.

Ideal Heat Engine Carnot Efficiency

Find the reversible heat-engine efficiency limit between two reservoir temperatures, using absolute temperature internally.

Ideal LC Natural Resonance Frequency

Calculate the natural frequency of an ideal inductor-capacitor model and solve for either component.

Ideal Lever Force, Arms & Mechanical Advantage

Balance ideal lever moments and calculate force ratio from perpendicular effort and load arms.

Ideal Piston Pressure, Bore & Force

Calculate ideal piston force from positive pressure difference and a full circular bore area.

Ideal Rocket Delta-v from Exhaust Speed & Mass Ratio

Relate ideal velocity change to effective exhaust speed and initial/final mass using the Tsiolkovsky equation, with all four inverse paths.

Ideal Transformer Turns, Voltage & Current Ratio

Explore ideal transformer voltage and load-current magnitudes from a positive turns ratio.

Ideal-Gas Density, Pressure & Molar Mass

Relate ideal-gas density to absolute pressure, absolute temperature and molar mass, with paired mass and mole units.

Illuminance in Lux & Foot-Candles

Convert nonnegative illuminance between lumens per square meter and lumens per square foot.

Inductor Current & Stored Magnetic Energy

Calculate stored energy in a linear ideal inductor from positive inductance and signed current.

Inductor Reactance & Susceptance Magnitude

Calculate ideal inductive-reactance magnitude and its reciprocal at a positive frequency.

Insertion Loss from Power or Equal-Impedance Voltage

Calculate insertion loss from power or equal-impedance voltage using known measurements, selectable units and clear physical assumptions.

Inverting Buck-Boost Duty Cycle from Output Magnitude

Calculate inverting buck-boost duty cycle from output magnitude using known measurements, selectable units and clear physical assumptions.

Kilogram-Force, Newtons & Force Units

Convert kilogram-force, newtons and other force units using standard gravity and exact unit definitions.

Knudsen Number from Mean Free Path & Length

Calculate the dimensionless ratio of molecular mean free path to a chosen characteristic length, with inverse calculations.

Lift Force & Flow Coefficient

Relate positive lift force to fluid density, flow speed, reference area and dimensionless lift coefficient.

Light Travel Time & Distance

Convert propagation time and distance at vacuum light speed or a supplied positive speed up to that limit.

Light Travel Time & Distance in Julian Years

Convert travel time to distance using the vacuum speed of light or a lower positive propagation speed, with astronomical units.

Linear Momentum Components & Vector Magnitude

Calculate one-dimensional momentum or three Cartesian momentum components and magnitudes from positive mass and signed velocities.

Linear Spring Restoring Force & Displacement

Calculate the signed restoring force of an ideal passive spring from its stiffness and change in length.

Linear Spring Stored Energy

Calculate elastic energy in an ideal linear spring from its stiffness and signed displacement from equilibrium.