Curent Events, Electricity, Electronics, Engineering, Physics, Simon's sketch book, Together with sis

Discussing the news: dangers of shorting your mobile

Today we have heard about a new accident involving a teenager electrocuted by her mobile phone. Luckily, this time it was not a lethal case, but a quick search on the web has revealed that this is no joke: several teens have died in just a few years because they were either holding their phone with wet hands while the phone was being charged at the same time, or dropped their phone into the bath tub while the phone was plugged in, or because they were using wired headphones while charging their phone!

At first Simon and I didn’t believe this could be so dangerous, as he knew for sure that a mobile phone adaptor always has a voltage control built into it that reduces the voltage from 220V to something like 5 to 20V. But then we dove into it and found out that apparently, once a short circuit occurs, the adaptor’s voltage control unit also malfunctions and lets the 220V current through!

Simon’s drawing of the adaptor

Crafty, Math and Computer Science Everywhere, Notes on everyday life, Simon makes gamez, Simon's sketch book, Together with sis

Sinterklaas math game with “gingerbread buttons”

It’s Sinterklaas season in the Dutch-speaking world and, of course, as we have started baking the traditional spiced cookies called kruidnoten (“gingerbread buttons”) Simon didn’t want to miss an opportunity to play a version of peg solitaire with eatable pieces!

Simon has baked these himself (together with Neva)
the winning strategy
Simon mixing the right proportion of spices, grinding clove (then adding nutmeg, white pepper, ginger, cardamom and cinnamon)
Contributing, English and Text-Based Data, Lingua franca, Milestones, Notes on everyday life, Together with sis

Simon edits his sisters vlog and does the subtitles

Simon’s sister Neva has started a vlog and Simon, busy as he is, enjoys editing her videos. For the first 17-minute video he has also done all the subtitles (translating from Dutch to English), which was a project that took him two days and something like 7 hours of work! Neva, in her turn, has got Simon increasingly interested in environmental issues.

Simon doing the subtitles
If you could choose, when woud you like to live – now, in the past or in the future? This poetic portrait of what the new generation thinks about the future climate is a spontaneous talk that Oxiea Villamonte (Royal Art Academy of Antwerp) and her young friend Neva Houben (8) have recorded while taking a walk by the river.
Group, Milestones, Murderous Maths, Notes on everyday life, Set the beautiful mind free, Simon teaching, Together with sis

Social encounters

Such a pleasant play date last week with another eager learner. Simon shared his GeoGebra skills and some geometrical paper tricks, among other things. It’s heartwarming to see Simon blossom socially, he is growingly attentive to younger kids and generally engaging with people of various ages, as long as they show interest in anything Simon has an understanding of.

Crafty, Math Riddles, Math Tricks, Murderous Maths, Simon's sketch book, Together with sis

More Puzzles from Maths Is Fun

In an earlier post, I have mentioned that for many games he programs Simon got his inspiration from the site Maths Is Fun. Perhaps I should add that at our home, Maths Is Fun has become an endless source of fun word problems, too! The problem below has been our favourite this week:

Simon’s equations to solve the problem
Simon has developed a system to show the relation between the actual time a and time m that a mirrored clock would show: m = 12 – a
Another clock puzzle from Maths Is Fun
Simon’s solution
solving this during his evening tea

Some of the puzzles Simon likes to recreate with paper and scissors rather than program:

A version of Connect 4 but this time with the tables of multiplication! Every player is only allowed to move one paper triangle at a time (the triangles indicate which two numbers one can use to get the next product in the table). The one who colours four products in a row wins.
As the game progresses it gets trickier

For the jug puzzle game, Simon has developed a graph plotting the winning strategy (analogous to what he once saw Mathologer do for another game).

Double-sided numbers, sort of a two-dimensional cellular automaton. The objective is to get to a state when all the numbers would be one colour. The rule: if a cell changes its colour, its four neighbours (not diagonal) also change colour. There’re also other versions of this puzzle with more difficult initial conditions.
A number-guessing game based on binary representation. When he was 8 years old, Simon programmed a similar trick in Processing. He also developed the same sort of trick for base 3 numbers.

Simon and Neva have also especially liked the Tricky Puzzles section (puzzles containing jokes).

Crafty, Electricity, Electronics, Engineering, Experiments, Geometry Joys, Notes on everyday life, Physics, Simon teaching, Together with sis

Vanishing Letters

Simon’s way to celebrate Helloween: a little demo about how red marker reflects red LED light and becomes invisible. A nice trick in the dark!

We also had so much fun with the blue LED lamp a couple days ago when Simon discovered that it projects perfect conic sections on the wall! Depending on the angle at which he was holding the lamp, he got a circle, an ellipse, a hyperbola and a parabola! Originally just a spheric light source we grabbed after the power went out in the bathroom, in Simon’s hands the lamp has become an inspiring science demo tool.

Computer Science, Engineering, Good Reads, Math and Computer Science Everywhere, Murderous Maths, Notes on everyday life, Physics, Simon teaching, Simon's sketch book, Together with sis

Zutopedia, a fun Computer Science Resource

Through the whole moth of October, Simon really loved watching Computer Science and Physics videos by Udi Aharoni, a researcher at IBM research labs and creator of the Udiprod channel https://www.youtube.com/user/udiprod and the Zutopedia website http://www.zutopedia.com/ Simon’s favourite has been the Halting Problem video that he also explained to his little sister.

In the example below, Simon has applied a compression algorithm to a sentence by transforming the sentence into a tree where all the letters have their corresponding frequencies in this sentence. “Can you get back to the sentence? You have to first transform the letters into ones and zeros using the tree (the tree is a way to encode it into ones and zeros that’s better than ASCII)”.

Simon learned this at http://www.zutopedia.com/compression.html
thanks to the Udiprod channel, Simon has also revisited sorting algorithms and spent hours comparing them, this time using self-made number cards
Crafty, Experiments, motor skills, Physics, Together with sis

Some Physics Demos with Geomag

Rotating a merry-go-round with a “magic wand”
One beautiful thing about Simon’s recent return to Geomag is that, as it turned out, he is now capable of building all the tricky constructions on his own, without any help from the grown-ups
An example of a Gaussian Gun, a magnetic chain reaction to launch a steel ball at high speed. As soon as the rolling ball hits the magnet, another ball in the opposite side is launched.