Interactive Physics Learning
About PhysicStuff
PhysicStuff is a physics site where the figures move. Every post comes with a simulation you can push on, because a formula you have dragged a slider through stays with you longer than one you have only read.
Why the site is printed in four inks
In 1847 the Irish engineer Oliver Byrne published an edition of Euclid in which the lines and angles of each proof were printed in red, blue and yellow instead of being labelled with letters. A reader could follow an argument by colour alone, without hunting for point B in the diagram. The book was a commercial failure and is now a design classic.
This site borrows the idea for physics. Four inks, four meanings, never swapped:
- Red is anything that moves or flows: velocity, current, frequency, the rate of a thing.
- Blue is where things are and the paths they take: displacement, orbits, rays.
- Yellow is how much: energy, heat, height, the area under a curve.
- Black is time, and whatever is fixed: the ground, the axes, the clock. In the night edition it prints white.
Once you have read one figure this way, you can read all of them. A red arrow is always a velocity. A yellow bar is always an amount of something. The equations are set in the same inks, so R = v2 sin 2θ / g can be read against its figure without a key.
The night edition. The switch in the running head turns the paper near-black and the ink off-white. Red and blue are lifted so they still read; yellow goes a shade deeper. The meanings do not change, and every figure redraws itself in the same palette as the page.
Reading on a phone. Figures sit under the heading and pin there while you drag the controls below them, so the thing you are changing stays in view.
Credit. Oliver Byrne, The First Six Books of the Elements of Euclid, in which coloured diagrams and symbols are used instead of letters for the greater ease of learners, London: William Pickering, 1847, printed by Charles Whittingham at the Chiswick Press. The book is in the public domain. The inks on this site are a tribute to it, not a reproduction.
About me
I’m Pratik Barve, and I write, code and design everything on PhysicStuff myself. I studied physics (B.Sc. and M.Sc.) at the University of Mumbai and data science (M.Sc.) at South East Technological University in Carlow, Ireland. I currently work as a Senior Data Engineer at AIB, and I’m an amateur astronomer and astrophotographer.
PhysicStuff started as a collection of Python and Jupyter notebooks, my personal record of physics concepts explored through code. The trouble with notebooks is that you have to run them yourself, so I rebuilt every simulation to run in your browser, with no setup.
There’s no team, no sponsor and no advertising at present. If a figure or calculation is wrong, please get in touch; I’d like to hear about it.
Keep learning!
New posts by email, and a lecture video for most of them on YouTube.