Free online science and maths tools

Roller coaster car attached to a spring while rolling on a track.

Simulates a simple pendulum with graphs of angle, velocity and energy.

Models three atoms joined by springs to show vibration modes.

Solves the wave equation on a string and shows how it vibrates.

Tests strong and weak acids and bases to see ion counts, pH and conductivity.

Practice balancing equations by adjusting coefficients with a visual atom count.

Shines light through colored solutions to relate concentration, path length and absorbance.

Shows refraction and reflection of light between media and with prisms and lenses.

Adjusts temperature to show how blackbody spectrum and peak wavelength shift.

Assembles molecules from atoms to meet collection targets and view 3D structure.

Add protons, neutrons and electrons to a model atom and watch which element, charge and mass result.

Lets you assemble batteries, bulbs, resistors and switches into DC circuits and read meters.

Collides balls in one or two dimensions and checks momentum and energy conservation.

Mixes colored light to show how the eye perceives color.

Compares masses and volumes of blocks in water to explore how density affects floating.

Tracks energy as it moves between heating, light and motion in a set of linked systems.

Moves a skater on adjustable tracks to show kinetic, potential and thermal energy.

Moves a magnet through a coil to induce current and light a bulb.

Pulls and pushes objects to explore net force, friction and acceleration.

Pumps gas into a container to explore pressure, volume and temperature relations.

Simulates orbiting bodies such as Sun, Earth and Moon so you can change masses and watch paths.

Shows how greenhouse gases change the energy balance of the atmosphere.

Stretches springs to show force, displacement and spring constant relations.

Hangs masses on springs to study oscillation, spring constant and energy.