72 tools
Physics
Motion, forces, energy, momentum, rotation, waves, light and radioactivity — the physics formulas used in school and at work.
Tools in this category
- PhysicsSpeed, Distance and Time CalculatorFill in any two of speed, distance and time and get the third.
- PhysicsKinematics CalculatorGive any three of starting speed, final speed, acceleration, time and distance, and the other two come out.
- PhysicsAcceleration CalculatorAverage acceleration from a change in speed over a time, with the distance covered.
- PhysicsFriction Force CalculatorThe force friction is actually applying, what it takes to break an object free, and how far it slides to a stop.
- PhysicsInclined Plane CalculatorThe forces on a slope: what pulls down it, what presses into it, whether it slides, and the force to hold or raise it.
- PhysicsCollision CalculatorThe speeds after a collision, elastic, inelastic or anywhere in between, with the energy that survives and the energy that does not.
- PhysicsKinetic Energy CalculatorEnergy of a moving object, plus the height it would have to fall to gain the same energy.
- PhysicsRope Tension CalculatorThe tension in a rope for the four cases that come up: hanging, in a lift, over a pulley, and shared between two ropes.
- PhysicsMoment of Inertia CalculatorRotational inertia for the standard shapes, with the parallel axis theorem, radius of gyration and stored energy.
- PhysicsFree Fall CalculatorDistance fallen and speed reached after a given time of free fall.
- PhysicsCentre of Mass CalculatorThe balance point of several masses along a line or across a plane, with each one's share of the total.
- PhysicsWork and Power CalculatorWork done by a force over a distance, and the power that implies over a time.
- PhysicsSpherical Mirror CalculatorWhere a concave or convex mirror puts the image, how big it is, and whether it is real, virtual, upright or inverted.
- PhysicsPotential Energy CalculatorGravitational potential energy at a height, and the speed it converts into.
- PhysicsSound Level and Distance CalculatorSound level at a new distance, the intensity and pressure behind it, and the level from several identical sources.
- PhysicsTime Dilation and Length Contraction CalculatorLorentz factor at a given fraction of light speed, with the stretched time, the shortened length and the kinetic energy.
- PhysicsDrag Force Calculator (Air Resistance)Aerodynamic drag on a car, bike or any object at a given speed, the power needed to overcome it and the energy it costs per 100 km.
- PhysicsHalf-Life CalculatorQuantity remaining after radioactive decay, the number of half-lives elapsed and the decay constant.
- PhysicsHooke's Law Spring CalculatorForce in a spring at a given extension, the energy stored, the sag under a mass and the natural frequency.
- PhysicsWavelength CalculatorWavelength from frequency and wave speed, including the quarter-wave length.
- PhysicsMass-Energy Equivalence CalculatorEnergy locked in a given mass, expressed in joules, kilowatt-hours and tonnes of TNT.
- PhysicsMomentum and Impulse CalculatorMomentum of a moving mass, and the force needed to change it in a given time.
- PhysicsProjectile Range CalculatorHow far, how high and for how long a projectile travels, from launch speed and angle.
- PhysicsCoulomb's Law CalculatorElectrostatic force between two point charges, the field of the first, and their potential energy.
- PhysicsGravitational Force CalculatorAttraction between two masses and the acceleration the larger one produces.
- PhysicsPhotoelectric Effect CalculatorMaximum kinetic energy and speed of the electrons knocked out of a metal by light, the stopping voltage, and the threshold wavelength and frequency.
- PhysicsBanked Curve Speed CalculatorDesign speed of a banked curve with no friction, the maximum speed with grip, and the flat-road limit.
- PhysicsDoppler Effect CalculatorFrequency heard as a source approaches and as it recedes, with the shift in hertz and semitones.
- PhysicsThin Lens Equation CalculatorImage distance, magnification and image height for a thin lens, plus its optical power in dioptres.
- PhysicsMagnetic Field Around a Wire Calculator (Ampère's Law)Magnetic field at a given distance from a straight wire carrying a current, in microtesla and gauss, compared with the Earth's field.
- PhysicsEscape Velocity CalculatorSpeed needed to escape a body's gravity, and the speed needed to orbit it at the surface.
- PhysicsSnell's Law Refraction CalculatorAngle of refraction between two media, the critical angle and the speed of light in each.
- PhysicsLorentz Force CalculatorMagnetic force on a moving charge, the radius it curves through and its cyclotron frequency.
- PhysicsPhoton Energy CalculatorEnergy of a photon from its wavelength, in electronvolts, attojoules and kilojoules per mole.
- PhysicsSpeed of Sound CalculatorSpeed of sound in air at a given temperature, the travel time over a distance and the echo rule.
- PhysicsAngular Momentum CalculatorAngular momentum and rotational energy, and the new speed if the moment of inertia changes.
- PhysicsPendulum Period CalculatorSwing period and frequency of a simple pendulum, plus the length for a one-second period.
- PhysicsForce on a Current-Carrying Wire CalculatorForce a magnetic field exerts on a wire carrying current, in total and per metre.
- PhysicsStanding Wave and Harmonics CalculatorResonant frequency of a string or open pipe at a chosen harmonic, and the closed-pipe frequency alongside.
- PhysicsBeat Frequency and Tuning CalculatorBeat rate between two close frequencies, the time between beats, and the interval in cents.
- PhysicsBounce Height Calculator (Coefficient of Restitution)Height of a ball after any number of bounces, the total distance and time until it stops, and the coefficient of restitution from a drop test.
- PhysicsElectromagnetic Wave Speed Calculator (Maxwell)Speed of an electromagnetic wave in a material, its velocity factor, refractive index, wavelength and wave impedance from εr and µr.
- PhysicsGauss's Law Calculator (Charged Sphere)Electric field, potential and flux at any distance from a charged sphere, inside or outside it, with the field profile drawn.
- PhysicsLensmaker's Equation CalculatorFocal length and power of a lens from its glass, the two radii of curvature and the thickness, in air or in another medium.
- PhysicsGravitational Time Dilation Calculator (GPS Clocks)How many microseconds per day a clock gains at altitude from weaker gravity, how many it loses to orbital speed, and the net drift of a clock in that orbit.
- PhysicsClimbing Fall Factor and Impact Force CalculatorFall factor of a lead fall and an idealised estimate of the peak force on the climber, from the fall length, the rope out and the rope's rated impact force.
- PhysicsOptical Fibre Numerical Aperture CalculatorNumerical aperture, acceptance angle, V number and single-mode cut-off of a step-index optical fibre from its core and cladding indices.
- PhysicsApparent Depth Calculator (Why Pools Look Shallow)How deep water looks from above compared with how deep it really is, and the size of Snell's window — the circle of sky a diver or fish sees overhead.
- PhysicsDecibel Addition Calculator (Combining Sound Levels)Combined sound level of two, three or four sources of different loudness, and how much louder the total is than the loudest one.
- PhysicsDiffraction Grating Calculator (Angles of the Orders and Spot Positions)Angles at which a diffraction grating sends a given wavelength in the first three orders, the highest order that exists, and where the spots land on a screen.
- PhysicsDouble-Slit Interference Calculator (Young's Experiment)Fringe spacing, the angle of the first bright fringe and the brightness anywhere on the screen, with the whole interference pattern drawn.
- PhysicsFloating Draft Calculator (Barge, Pontoon, Flat-Bottom Boat)How deep a flat-bottomed box, pontoon or barge sits in the water for a given load, the freeboard left, and the most it can carry before the water reaches the deck.
- PhysicsMagnifier Calculator (Magnifying Glass Power from Focal Length)Magnification of a magnifying glass or loupe from its focal length, in both common conventions, with its power in dioptres — or the focal length for a stated magnification.
- PhysicsPlanck's Law Calculator (Black-Body Spectrum)Spectral radiance of a black body at any wavelength and temperature, its peak and total emission, with the whole spectrum drawn against a second temperature.
- PhysicsRolling Down an Incline Calculator (Sphere, Cylinder, Hoop Race)Acceleration, speed at the bottom and time for a sphere, cylinder or hoop rolling down a slope, and the friction needed so it does not slip.
- PhysicsDe Broglie Wavelength CalculatorThe matter wavelength of a particle from its mass and speed, in metres, nanometres and picometres.
- PhysicsAdiabatic Compression and Expansion Calculator (Ideal Gas)Final temperature, pressure and work when an ideal gas is compressed or expanded so quickly that no heat flows in or out, with the isothermal result for comparison.
- PhysicsBallistic Pendulum Calculator (Speed of a Projectile)Speed of a bullet or ball from how far a hanging block swings after catching it, with the height risen and the share of energy lost in the impact.
- PhysicsFresnel Equations Calculator (Reflectance and Brewster Angle)How much light a surface between two materials reflects at any angle, for each polarisation, with the Brewster and critical angles and the full curve drawn.
- PhysicsGravity at Latitude and Altitude Calculator (Local g)The acceleration of gravity at your latitude and height above sea level, how much a given mass weighs there and how fast the Earth's rotation carries you along.
- PhysicsHelmholtz Coil CalculatorMagnetic field along the axis of a pair of coaxial coils, how uniform it is around the middle, and the field profile of each coil drawn.
- PhysicsGas Molecule Speed and Mean Free Path Calculator (Kinetic Theory)How fast the molecules of a gas move at a given temperature, three ways of averaging it, and how far a molecule travels between collisions.
- PhysicsMalus's Law Calculator (Polarisers)Light intensity after one, two or three polarisers at any angles, with the classic three-polariser surprise shown on the chart.
- PhysicsNuclear Binding Energy Calculator (Mass Defect and Energy per Nucleon)The energy that holds a nucleus together, from its measured atomic mass: the mass defect, the total binding energy in MeV and the binding energy per nucleon.
- PhysicsPoiseuille Flow Calculator (Hagen–Poiseuille Law for Tubes and Blood Vessels)Flow rate of a thick liquid through a narrow tube from the pressure difference, tube size, length and viscosity, with a check that the flow is smooth enough for the law to hold.
- PhysicsRadiation Pressure and Solar Sail CalculatorForce, pressure and acceleration that sunlight produces on a sail at a given distance from the Sun, for any reflectivity and tilt.
- PhysicsRainbow and Halo Angle Calculator (Why 42° and 22°)The angle from the point opposite the Sun at which the primary and secondary rainbows appear for red and violet light, the dark band between them, and the 22° halo of ice crystals.
- PhysicsRelativistic Kinetic Energy CalculatorKinetic energy, Lorentz factor and momentum of an object moving at a sizeable fraction of the speed of light, compared with Newton's ½mv².
- PhysicsRelativistic Velocity Addition CalculatorCombined speed of an object moving inside a moving frame, by Einstein's formula, compared with the simple sum.
- PhysicsThin Film Interference Calculator (Soap Bubbles, Oil Slicks, Anti-Reflection Coatings)Wavelengths a thin film of a given thickness and refractive index reflects most strongly, the thinnest film that makes or cancels a reflection, and its brightness at one wavelength.
- PhysicsCapillary Rise Calculator (Jurin's Law)How high a liquid climbs, or is pushed down, in a narrow tube from its surface tension, the contact angle, the density and the tube radius.
- PhysicsCompton Scattering CalculatorEnergy and wavelength of a photon after bouncing off an electron, the energy the electron takes, and the Compton edge and backscatter peak of a gamma line.