Basic skills
Quantities and unitswhy 20,000 is not more than 10,0007:30
Ratios and percentagesone table for both3:15
Scientific notationpowers of ten and order of magnitude5:22
Calculating with powers of tenthe four rules3:18
Pythagoras and trigonometrywhich side with which angle3:19
Deriving units from a formulaconverting to base units7:47
Significant figureshow many figures do you write6:24
Line of best fitthe line touches no point5:07
Relationships and the constantbraking twice as fast5:20
Linearising a graphyour measurements never change4:41
About me

My name is Thomas Schuurmans, and I have a passion for physics and for understanding why things work the way they do. What I want is to get young people asking “why is that?” and “how does that work?” more often, and to hand them the tools of physics in a way that is simple and that you can see.
I graduated in applied physics at Delft University of Technology in 2003. After that I spent more than twenty years outside education: first at TNO, the Dutch applied research institute, then at a design agency, and eventually founding Proportion Global, through which I work on innovation questions in Africa, Latin America and South Asia. That work resembles physics more than you would expect: don't start from a solution, first understand what is going on, try something, be wrong, and look again.
Proportion Global now works with a network of local consultants in 67 countries, so I hardly need to travel myself any more. That gives me more time, and more of a need, to make a difference closer to home as well. So I picked up my old love for physics again. Since September 2026 I have been teaching physics two mornings a week at the Cartesius Lyceum in Amsterdam, to lower and upper secondary classes.
I am very much a visual learner myself when I want to learn something new. That is where the idea came from: videos that explain one topic sharply and visually, in just a few minutes. I make them for my own pupils. Then I publish them, because a good explanation should be within reach of anyone who needs it, wherever you live and whatever language you think and speak in.








