Interactive explainers

How a lithium-ion battery works

Li⁺ and electrons on charge vs discharge, SOC-gated current with Empty/Full stat

Electrolysis of water

Splitting 2H₂O → 2H₂ + O₂ — H₂ collects at exactly twice the volume of O₂, with

Enzyme kinetics — lock & key

An enzyme binds its substrate, makes product and is reused; Michaelis–Menten v =

Neuron action potential

How a neuron fires all-or-none: Na⁺ then K⁺ gates drive Vm −70→+40→−70 mV, with

4-stroke engine cycle

Intake→compression→power→exhaust over 720° — one crank angle drives piston, valv

DNA — the double helix

How the two strands pair and twist, with live base-pair counts and narration.

Bouncing ball & restitution

Why a ball never bounces back to the height it was dropped from.

Kepler's equal-areas law

A planet sweeps out equal areas in equal times — faster near the Sun.

Why the sky is blue

Rayleigh scattering paints a blue sky and a red sunset.

Simple pendulum — measuring g

How period depends on length, and how it reveals gravity.

Step-up transformer

An iron core couples primary→secondary; Vs = Vp·(Ns/Np) steps voltage up while c

Photosynthesis — sunlight to glucose

Sun→leaf CO₂/O₂, then the chloroplast light & CO₂-fixation chemistry: 6CO₂ + 6H₂

Cyclotron — moving charge in a field

A charge spirals faster but circles at the same rate — real-3D, with narration.

Solenoid — the field of a coil

How turns of current build a uniform magnetic field inside a solenoid (3D).

Torque on a current loop

Why a current loop twists in a magnetic field — the motor principle (3D).

Kepler's law of areas

A planet sweeps equal areas in equal times — orbit it in real 3D, with narration

Escape speed

How fast must you launch to never fall back — v = √(2GM/R), shown in 3D.

Gravitational field inside & outside a planet

Why g peaks at the surface and falls both ways from it (3D).

Energy of an orbiting satellite

How kinetic, potential and total energy trade off around an orbit (3D).

Bohr orbits — rₙ = n²a₀/Z

Why electron orbits sit at fixed radii, shown in real 3D with narration.

de Broglie waves — why orbits are quantised

Standing electron waves explain why only certain orbits survive (3D).

Energy levels — the ladder and its jumps

How electrons jump rungs and emit light of a definite colour (3D).

Rutherford scattering — finding the nucleus

Why a few alpha particles bounce straight back — the nucleus revealed (3D).

Conservation of angular momentum

The spinning skater speeds up as she pulls her arms in — real 3D, narrated.

Moment of inertia — I = Σmr²

Why mass farther from the axis is harder to spin (3D).

Rolling without slipping — v = ωR

How spin and translation lock together for a rolling body (3D).

Gyroscopic precession

Why a spinning top leans and circles instead of falling (3D).

Coulomb's law — two charges, one force law

How force scales with charge and distance, shown in real 3D with narration.

Electric field — what a source does to space

The field a charge sets up everywhere around it (3D).

Electric field lines

Reading a charge configuration at a glance from its field lines (3D).

Electric flux

Counting the field lines that cross a surface (3D).

Gauss's law — field of a charged sphere

Why the field inside is zero and outside looks like a point charge (3D).

Electric dipole

Torque, oscillation and the 1/r³ field of a dipole (3D).

Einstein’s Photoelectric Equation: Energy Quantum of Radiation

Physics

Interference of Light Waves and Young’s Experiment

Physics

Refraction through a Prism

Physics

Electromagnetic Spectrum

Physics

Faraday’s Law of Induction

Physics

Magnetic Field due to a Current Element, Biot-Savart Law

Physics

Photoelectric Effect and Wave Theory of Light

Physics

Experimental Study of Photoelectric Effect

Physics

Alpha-particle Scattering and Rutherford’s Nuclear Model of Atom

Physics

Kirchhoff’s Rules

Physics

Classification of Crystalline Solids

Chemistry

Collision Theory of Chemical Reactions

Chemistry

Pythagorean theorem by rearrangement: a big square of side a+b is cut into a square of area a squared, a square of area b squared and two a-by-b rectangles; the same big square is then shown as four c

Maths

Paper Chromatography

Chemistry

Sterilization of Water Using Bleaching Powder make the experiment with the animation for better understanding

Chemistry

show how probability works

Maths

Maxima and minima — optimising with the derivative

Maths

Ideal gas law — PV = nRT derived from kinetic theory

Physics

Nernst equation — how concentration and temperature shift cell potential

Chemistry

Water self-ionisation and Kw — amphoteric behaviour and pH at 25°C

Chemistry

Reaction mechanisms and the rate-determining step

Chemistry

Calorimetry — measuring heat with q = mcΔT

Chemistry

Gibbs free energy — ΔG = ΔH − TΔS and the spontaneity condition

Chemistry

Resting membrane potential — why neurons sit at −70 mV and how it is maintained

Biology

Snell's law — refraction, critical angle and total internal reflection

Physics

Torque and rotational equilibrium — lever arm, conditions for static balance

Physics

Glycolysis — glucose to 2 pyruvate, net ATP yield and key enzymes

Biology

Rate laws and reaction order — how concentration affects reaction rate

Chemistry

Entropy and the second law of thermodynamics — disorder and spontaneity

Chemistry

Transcription — copying DNA to mRNA, RNA polymerase and promoters

Biology

Gene mutations — point mutations, frameshifts and their biological consequences

Biology

Conservation of momentum — elastic and inelastic collisions solved live

Physics

Wave superposition and double-slit interference — constructive and destructive fringes

Physics

Single-slit diffraction — Huygens principle and fringe spacing

Physics

How a rainbow forms by refraction and dispersion of sunlight in a raindrop

Physics

Archimedes' principle: why objects float (buoyancy and displaced water)

Physics

The Doppler effect: why a passing ambulance siren changes pitch

Physics