Einstein as a speed devil - science puzzle
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
How fast should you drive towards a red traffic light to see it appear as green? |
![]() |
Somewhere on a sphere - math puzzle
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
What is the mean distance between two randomly choosen points within a sphere of radius 1?
Platonic solids - math puzzle
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
![difficulty](http://www.nuin.nl/rdzl/assets/images/star_yellow.png)
Show that there exist only five platonic solids (that are objects which are build out of the one sort of regular polygons, like the tetrahedron and the cube). Hint: use that for each solid in three dimensions it holds that the number of vertices + the number of faces is equal to the number of edges + 2. |
![]() |