Physics Calculators

Enter speed change, force and mass, or circular motion values to calculate acceleration. Get step-by-step solutions, g-force, and a velocity-time graph.

Convert angular velocity between RPM, rad/s, deg/s, Hz, rev/s and rotation period, or work it out from linear speed and radius. Also gives tangential speed and centripetal acceleration at any radius, with a spinning-disk animation.

Calculate the belt length that connects two pulleys from their diameters and centre distance. Supports open and crossed drives and gives the exact and textbook lengths, wrap angle on each pulley, speed ratio and driven RPM.

Solve the Bernoulli equation along a streamline for pressure, flow velocity or elevation at either point. Includes a step-by-step breakdown, an animated streamline diagram and an energy grade line chart, for water, air, oil and more.

Calculate the boiling point of water at different altitudes, elevations, or atmospheric pressures using the Clausius-Clapeyron equation. Includes step-by-step solutions and interactive altitude chart.

Enter fluid density, object volume, and mass to determine whether an object floats or sinks, its buoyant force, apparent weight, and submerged percentage.

Solve F = mv2/r for centripetal force, mass, radius or speed. Switch between linear speed (m/s, km/h, mph) and angular inputs (rad/s, RPM, period), and read the g-force, period, angular velocity and the tire grip a turn needs.

Compute the electrostatic force between two point charges with Coulomb's law. Solve for force, either charge or distance, choose charge units and a dielectric medium, and read direction, electric field and potential energy.

Enter mass and velocity, or kinetic energy, to get the de Broglie wavelength from relativistic momentum and a wave-versus-classical comparison.

Enter mass and volume to get density, or density and one known value to get the missing mass or volume, with units, steps and material comparisons.

Calculate the observed frequency, wavelength change and pitch shift when a source moves relative to an observer. Supports classical sound and relativistic light Doppler, several media, a live animation and an audio pitch preview.

Calculate the energy locked in any mass with E=mc2, or work backwards from energy. See joules, kilowatt-hours and tons of TNT translated into everyday comparisons, with efficiency presets for antimatter, fusion and fission.

Place up to six point charges and a test point to get field components, magnitude and direction, plus force on a probe charge and potential.

Calculate voltage, current, resistance, and power using Ohm's Law and Watt's Law. Enter any two known values and instantly solve for the other two with detailed step-by-step formulas.

Calculate static compression ratio from bore, stroke, chamber volume, head gasket, deck clearance and piston dome or dish. Shows displacement, a swept-versus-clearance breakdown and which fuel octane your ratio needs.

Enter bore, stroke and cylinder count to get displacement in cc, litres and cubic inches, per-cylinder volume, and oversquare, square or undersquare.

Calculate the escape velocity of any planet, moon, star or custom body from its mass and radius. Pick Earth, the Moon, Mars, Jupiter, the Sun or a neutron star, and see km/s, mph and Mach on a ladder from a sprinter to light speed.

Calculate force, mass, or acceleration using Newton's second law F=ma. Enter any two values to solve for the third, with unit conversions and real-world force comparisons.

Calculate the velocity, distance, and time for objects in free fall under gravity. Supports multiple planets and provides step-by-step solutions with trajectory data.

Calculate static and kinetic friction force from the normal force or mass and the coefficient of friction. Add an applied push to see whether the object stays put or slides, its acceleration, and the angle of repose.

Calculate the gear ratio, output speed and output torque of a gear system from the teeth on the driving and driven gears. See an animated pair of gears turning at the real ratio, the simplified ratio and the mechanical advantage.

Calculate the gravitational force between two masses with Newton's law. Solve for either mass or the distance, choose units from grams to solar masses, and load scenarios like the Earth and Moon, with an inverse-square force curve.

Enter mounting height, downward aim angle, and driving speed to calculate the headlight beam reach, lit zone, and safe stopping distance.

Enter material dimensions, temperatures, and thermal properties to calculate conduction, convection, or radiation rates in watts and heat flux.

Calculate engine horsepower from torque and RPM, or solve for any unknown. Supports Imperial (lb-ft, HP) and Metric (Nm, kW) units with step-by-step solutions and unit conversions.

Calculate the push and pull force a hydraulic cylinder produces from system pressure, bore diameter and rod diameter. See a cross-section, the piston and annulus areas, the extend/retract ratio, and results in N, kN, lbf and kgf.

Calculate pressure, volume, moles, or temperature using the ideal gas law equation PV=nRT. Supports multiple unit systems with step-by-step solutions and automatic unit conversions.

Enter mass, angle, and friction coefficients. See weight components, normal force, static and kinetic friction, acceleration, and whether it slides.

Enter the semi-major axis and central mass, in AU, kilometres, or solar or Earth masses. See the orbital period and mean orbital velocity.

Solve one-dimensional kinematics problems using the four kinematic equations. Enter any 3 known variables to find the 2 unknowns with detailed step-by-step solutions.

Enter any two of kinetic energy, mass, and velocity. Solve for the third in the units you choose, with steps and everyday energy comparisons.

Solve the thin-lens equation to find focal length, object distance, image distance, magnification and image height. Tells you whether the image is real or virtual, upright or inverted, with a live ray diagram for both lens types.

Enter current and distance for a straight wire, a circular loop on axis, or a solenoid. Get the magnetic field, with an optional core on the solenoid.

Calculate the mechanical advantage of a lever, pulley system, inclined plane or gear train. Get the ideal and efficiency-adjusted figures, the effort force needed to move a load, the distance trade-off and an animated diagram.

Select a shape, choose area or mass inertia, and enter dimensions to compute moments of inertia, parallel-axis offsets, and section modulus.

Calculate linear momentum (p=mv), analyze elastic and inelastic collisions with conservation of momentum, and compute impulse. Step-by-step solutions with collision animation.

Enter length and gravity, or solve for period, length, frequency, or gravity, and compare the small-angle and elliptic results.

Calculate photon energy from a wavelength or frequency. Get the energy in joules and electronvolts, the matching frequency and wavelength, and the energy per mole, plus where the photon sits on the electromagnetic spectrum.

Calculate gravitational potential energy (PE = mgh) or elastic potential energy (PE = ½kx²). Supports multiple planets, unit conversions, and detailed step-by-step solutions.

Calculate pressure from force and area using P=F/A. Supports multiple unit systems (Pa, kPa, bar, atm, psi, mmHg) with step-by-step solutions, unit conversions, and real-world pressure comparisons.

Calculate projectile range, maximum height, time of flight, and full trajectory from launch angle and initial velocity. Supports custom gravity, initial height, and animated trajectory visualization.

Calculate the mechanical advantage, effort force and rope pull distance of a pulley system from the number of supporting rope segments. Includes an animated block-and-tackle diagram and a real-world friction model.

Enter velocity, length, density, and viscosity, and choose pipe, flat-plate, or open-channel flow. Get the Reynolds number and the flow regime.

Enter two refractive indices and an angle, or pick materials, to find the refraction angle, a missing index, the critical angle, or Brewster's angle.

Enter three of heat, mass, specific heat, and temperature change, or pick a substance, to solve Q = mcΔT for the missing one.

Calculate the speed of sound in air from temperature with an optional humidity correction, or look it up in water, steel, helium and dozens of other media. Get m/s, km/h, mph, ft/s and knots plus Mach 1 and lightning-to-thunder distance.

Enter force and displacement, or a hanging mass, for one spring or springs in series or parallel to get k, energy, period, and natural frequency.

Calculate a vehicle's total stopping distance from its speed, splitting reaction distance from braking distance, and see how dry, wet, snowy or icy roads change it. Includes a braking animation and driver-reaction presets.

Calculate the terminal velocity of a falling object from its mass, drag coefficient and cross-sectional area. Pick a skydiver, raindrop, bowling ball or feather, choose air, water or honey, and see how far it must fall to reach it.

Calculate the change in length, area or volume caused by a temperature change. Pick a material or enter your own expansion coefficient, set the start and end temperature, and see the expansion, final size, strain and a diagram.

Calculate relativistic time dilation, the Lorentz factor and length contraction at any velocity. Enter a speed as a fraction of light, km/s or mph to see how much slower a moving clock ticks and how far apart two travellers would age.

Calculate torque from force and lever arm distance using τ = F × r × sin(θ). Solve for any unknown variable with detailed step-by-step solutions, unit conversions, and real-world torque comparisons.

Calculate average or relative velocity from distance and time values, and convert instantly between m/s, km/h, mph, ft/s, and knots.

Use the wave equation to solve for wave speed, frequency or wavelength. Enter any two values with flexible units to get the third plus period, angular frequency and wavenumber, with a live traveling wave and spectrum band detection.

Calculate work done by a force (W = Fd cosθ) and mechanical power (P = W/t). Supports multiple units, angle input, and provides step-by-step solutions with energy comparisons.