Physics Playgrounds vs Start Physics

Physics Playground is a hands-on science app with 102 interactive labs — from pendulums and black holes to rainbows, magnets and melting ice. Every lab is a live simulation you control with your finger, or with your hand in the air, so you can see how the world works instead of just reading about it. THREE WAYS TO EXPLORE • Explore — pick any lab and start playing. • Learning Journey — follow a short story one step at a time: Things that move, Light and sound, Earth and space. • Curiosity Lab — ask your own science question by typing or speaking and get a short, friendly answer. Tap "Draw it!" for a picture, save pictures to Photos, or have the answer read aloud. 102 LABS How the World Works (44 labs): Colour Mixer, Rainbow Spinner, Heavy or Light?, Drop Zone, Slide Race, Bouncy Balls and many more everyday science experiments Mechanics: Simple Pendulum, Projectile Motion, Elastic Collision, Spring Oscillator, Inclined Plane, Pulley System, Circular Motion and more Waves and Sound: Wave Interference, Doppler Effect, Standing Waves, Resonance Studio Light and Optics: Light Refraction, Light Reflection, Light Polarization, Rainbow Maker Electricity and Magnetism: Electric Field, Capacitor Charging, Circuit City, Magnet Maze, Electromagnetic Induction, Tesla Coil Heat and Matter: Gas Particles, Entropy & Disorder, Tiny Heat Engine, Crystal Builder, Phase Changer Quantum and Nuclear: Double Slit, Photoelectric Effect, Quantum Tunnel, Radioactive Decay, Nuclear Fission, Nuclear Fusion, Half-Life Detective Space and Relativity: Orbital Mechanics, Black Hole, Exoplanet Hunter, Relativity Rocket, Gravity Lens Earth and Energy: Tectonic Plates, Weather Balloon, Solar Grid, Wind Tunnel Fluids: Fluid Flow, Buoyancy, Vortex Lab HOW IT WORKS Touch the canvas to grab and interact with the simulation — there is no right or wrong way to explore. Adjust variables like gravity, mass, length and velocity with the built-in sliders and watch the results change instantly. For a hands-free experience, turn on the camera and control labs with your hand in the air. Hand tracking runs on your device — no images or video are stored or sent anywhere. CHALLENGES Every lab has a challenge that teaches the key idea behind it. Complete it to earn a star and track your progress across all 102 labs on the progress screen. REAL PHYSICS LAWS The simulations are built on real physics equations, and the app shows the governing laws so you can connect what you see to real formulas. ABOUT CURIOSITY LAB Answers and pictures are created by AI (Google's Gemini models) for learning and fun, and can sometimes be wrong. Every answer has a Report button, and questions are limited each day. Curiosity Lab asks for your permission before it shares a question with Google Gemini, and you can turn this off at any time in Privacy choices. WHO IS IT FOR Students, teachers and anyone curious about how the physics world works — from first questions to university physics. It makes an excellent companion to classroom learning, and no prior knowledge is needed. PRIVACY Play as a guest — no name or email needed. A grown-up can choose to sign in with Apple or Google to keep progress across devices, and can delete the account in the app at any time. You decide whether to share usage analytics. Camera processing happens entirely on your device. Privacy policy: https://physics-playground-24c5e.web.app/privacy Terms: https://physics-playground-24c5e.web.app/terms

Study school physics in one flow: concepts, worked examples, practice, review. The app follows your device language —— English or Korean. Switch at any time; your records carry over. ■ It traces the gap If you keep missing conservation of mechanical energy and the real gap is in work and kinetic energy, solving the same problem a hundred more times will not help. This app gathers the concepts behind your wrong answers, walks back along the prerequisites to the weakest one, and tells you where to start again. A unit you reach this way opens its concepts and examples even when it is locked, and it stays open. Sometimes the gap is in math; the card then opens that unit in our Start Math app. ■ Constants are given inside the problem Some textbooks take gravitational acceleration as 9.8 m/s², others as 10. If the answer depends on which book you own, that is guessing, not study. Every problem states the constants it needs: "Take g = 10 m/s²." ■ A grader that knows units If the answer is 40 N, 0.04 kN is right too. Unit prefixes, conversions such as km/h to m/s, and tolerance for decimal answers are all handled, and every grading rule is covered by automated tests so that a right answer is never marked wrong. Questions never say "answer in newtons". The answer box shows the unit. Written answers accept the forms people actually write —— "valence band" or "the valence band", "3" or "3 times". ■ Wrong answers come back when you are about to forget Missed problems go into a review notebook and return after 1, 3, 7, 16 and 35 days. Get one right and the interval grows; miss it again and it starts over. You can mark why you missed it —— a slip in the math, an idea you misunderstood, or a question you misread. A slip does not lower your mastery of the concept, and it comes back in three days instead of one. ■ Formulas and diagrams are typeset, not pasted No formula is an image. Fractions, radicals and vector arrows are drawn by typesetting rules, so nothing blurs when you make the text larger. Free-body diagrams, circuits, magnetic fields, energy levels and ray diagrams for lenses —— 142 figures drawn from coordinates. With VoiceOver, formulas and units are read aloud the way a teacher says them —— "1 over 2", "meters per second squared". ■ Concepts you can move Six simulations —— resultant force, gravity and weight, elastic force, friction, buoyancy, and how a net force changes motion. Drag the values and watch what happens; it is quicker than reading about it. ■ What is inside · Middle School Physics (Grades 7–9) —— forces, heat, light and waves, electricity and magnetism, motion and energy (345 problems) · Integrated Science: Physics (Grade 10) —— foundations of science, mechanical systems, electrical properties of matter, power generation (263 problems) · Physics (Grade 11) —— equilibrium, momentum and energy, heat, electric fields and circuits, induction, light and lenses, quanta and matter (483 problems) · Mechanics and Energy (Career Elective) —— motion in a plane, gravity and space, heat and thermodynamics, oscillations and sound (345 problems) · Electromagnetism and Quantum Physics (Career Elective) —— electric fields, induction, semiconductors, light and communication, the quantum world (306 problems) 126 lessons, 1,742 problems (3 extras per lesson, 4 challenges per chapter), 146 concepts and a 211-entry glossary, all in English. Every problem was written for this app. The courses follow South Korea's 2022 national curriculum, including the limits its commentary sets —— where it says a topic is to be treated qualitatively, we do not ask for numbers. ■ Buying One purchase per course. Not a subscription, never expires, Family Sharing on. Without buying, the first two lessons of every chapter stay open —— 520 problems. ■ Requirements iOS 18.0 or later. No account. Works offline. Your study records stay on your device and in your own iCloud.