Physics № 01
Why is there a tiny hole in an airplane window?
The small hole in some airplane window panes connects a gap to the cabin—not the outside. Here is how that changes the pressure across the layers.
Simulations
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Space Interactive What if we replace the Sun?
Space Interactive Spin a space station: artificial gravity
Space Interactive Could we terraform Mars?
Physics Interactive The muon paradox
Space Interactive How small can you squeeze it?
Physics Interactive Orbits and Kepler’s laws
Space Interactive Scale of the universe
Planets Interactive Planet and star size comparison
Planets Interactive Weight on other planets
Space Interactive Moon phases: why does the Moon change shape?
Space Interactive Why do we have seasons?
Space Interactive Solar and lunar eclipse simulator
Earth Interactive How do tides work?
Space Interactive How long does it take to get to Mars?
Space Interactive Rocket equation: why is orbit so hard?
Physics Interactive Projectile motion simulator: which angle goes farthest?
Physics Interactive Pendulum period formula and simple pendulum simulator
Physics Interactive Half-life and radioactive decay simulator
Quantum Interactive Double slit experiment: waves, particles and watching the slits
Relativity Interactive The twin paradox: how much younger does the traveller return?
Light Interactive Snell’s law: how light bends, reflects and gets trapped
Space Interactive Roche limit simulator: turn a moon into rings
Space Interactive Lagrange points simulator: L1 to L5
Space Interactive Retrograde motion simulator: Mars and Mercury
Space Interactive Gravity assist simulator: a Jupiter flyby
Space Interactive Atmospheric escape simulator: can a planet keep its gas?
Relativity Interactive Gravitational time dilation simulator: black hole clocks
Space Interactive Redshift and blueshift simulator: spectral detective
Space Interactive Exoplanet transit simulator and light curve
Space Interactive Star life cycle simulator and H–R diagram
Space Interactive Orbital resonance simulator: repeating planetary rhythms
Physics Coming soon
How body shape changes lift
Featured
Latest posts
Space 01
One hour of astrophotography: why 240 short exposures can differ from six long ones
A reproducible Python noise budget compares equal total exposure times in two illustrative regimes—and shows why longer is not automatically better in the field.
Environment 02
A bigger kettle is not the problem. Heating extra water is
A reproducible Python model separates water volume, kettle power and assumed efficiency to show what changes the energy used for a cup of hot water.
Reviews 03
Science gifts for ages 8–12: a Snap Circuits kit or a MEL Science gift plan?
Choose a reusable electronics kit or a prepaid science delivery plan by the child’s interests, adult time and total commitment—with a US gift-plan link and country-specific availability checks.
Reviews 04
Which science-writing course do you need: clearer prose, stronger English or neither?
Compare Stanford’s Writing in the Sciences, Penn’s English for STEM and free writing resources, with a short diagnostic before you pay.
Space 05
Gravity is still strong at the space station. Why do astronauts float?
The station, crew and loose objects fall together. Weightlessness is about the missing support force, not gravity switching off above the atmosphere.
Physics 06
Metal and wood can be the same temperature. Why does only one feel cold?
Your hand feels heat leaving your skin, not just an object’s temperature. A simple comparison separates temperature, conductivity and misleading thermometer readings.