OU blog

Personal Blogs

Richard Walker

A Quick Geometric Problem

Visible to anyone in the world

Michael Penn put this up on his YouTube channel earlier today, and it is indeed an elegant little problem. Here it is


Michael Penn solves this using congruent triangles, the angle sum of a triangle (180 °) and angles on a straight line (180 °). α is always 60 °, whatever the length of AD and CE. It's not that obvious and I was quite surprised.

However thinking about it later, I saw we can solve the problem using symmetry and the solution is super-nice. Here's how - just add a third line.



Permalink Add your comment
Share post
Richard Walker

When we were very young

Visible to anyone in the world
When I was in infant school they taught us to read. The phonetic method was used (I see in hindsight), so “can” is “c” for cat, “a” for apple, and “n” for night, and there you have it. It doesn’t work very well, but it’s a good start.
 
There we were, two dozen or so, and we are reading Janet and John out loud. “L-o-o-k J-a-n-e-t s-a-y-s J-o-h-n”. It doesn’t totally work but if you listen to yourself, you can work out most words. The story helps a lot of course. 

Our teacher offered a gold star to the first person in the class who could read silently. I’m not a gold star person personally, and I was bored by it all. So to pass the time I stopped speaking and just pretended to be reading.

Wow big mistake! Up comes Teacher who says “Oh look class, Richard can read silently”. On the spot or what? From that time I couldn’t read out loud without being exposed as a fraud, and I more or less instantly found out I’d been able to read silently all along.

I’ve no idea what reminded me of this.

Permalink Add your comment
Share post
Richard Walker

A Reason for Optimism

Visible to anyone in the world


Permalink Add your comment
Share post
Richard Walker

At The Races

Visible to anyone in the world
Edited by Richard Walker, Friday, 20 Nov 2020, 22:13

Just been watching an Egg and Spoon race. Very surprised the Spoon didn’t win.

Permalink Add your comment
Share post
Richard Walker

Outlaws

Visible to anyone in the world

The authorities are after a couple of bad guys. Apparently they are Juan, Ted.

Permalink 1 comment (latest comment by Joanne Maddock, Friday, 20 Nov 2020, 19:31)
Share post
Richard Walker

One Liner

Visible to anyone in the world

grovellingapology.com

It’s a sorry site.

Permalink Add your comment
Share post
Richard Walker

Scarebears

Visible to anyone in the world

This fearsome creature is a robot wolf.


The city of Takikawa in Hokkaido has been having problems with bears venturing into the city after food.

So the city has invested in robot wolves with motion detectors. The robot wolves have bared teeth, flashing red eyes, and a repetoire of 60+ noises that bears find frightening. A bit like a mechanical scarecrow, but for bears.

You can see a robot bear in action here

https://www.theguardian.com/world/2020/nov/11/japanese-town-deploys-monster-wolf-robots-to-deter-bears



Permalink Add your comment
Share post
Richard Walker

How Big Was The Round Table?

Visible to anyone in the world
Edited by Richard Walker, Wednesday, 18 Nov 2020, 01:22

Thinking about the Round Table Puzzle 

https://learn1.open.ac.uk/mod/oublog/viewpost.php?post=232912

I wondered how many seats there are supposed to have been at the Round Table and whether communication (or even staying out of the rain) would have been feasible.

From the Wikipedia article Knights of the Round Table I got some useful information. Many have written about the Round Table, but among them the seating statistics can be summarised as follows

minimum 12
mode (commonest value); in the range 100-300, let’s say 200
maximum 1500+

What we want to know is the diameter of the table, and since this is only a back-of-an-envelope estimate we’ll say pi = 3. And ignoring social distancing it would be fair to assume each knight occupied 1 m of circumference.

My calculations

Minimum 12/3 = 4 m; big table, you’d need to shout; table easily fits indoors.
Mode 200/3 = 60+ m; loud hailers required; can be accommodated in a banqueting hall.
Maximum 1500/3 = 500 m (half a km!) ; telecoms required; only possible outside.

This post is a summarised preprint of a piece I plan to submit to Significance.
Permalink
Share post
Richard Walker

One liner

Visible to anyone in the world
Edited by Richard Walker, Tuesday, 17 Nov 2020, 22:07

My latest book is about turtles. It's only available in hardback.

Permalink Add your comment
Share post
Richard Walker

Supper Tonight

Visible to anyone in the world


The garnish on the noodle is a seaweed, aonori, also called green laver.

Permalink 2 comments (latest comment by Richard Walker, Tuesday, 17 Nov 2020, 22:11)
Share post
Richard Walker

A Riddle

Visible to anyone in the world

Q. What word is not the same as itself?

A. My answer: "Any word, apart from 'itself', but my favourite is 'sausage'."

Permalink Add your comment
Share post
Richard Walker

Contradicting oneself

Visible to anyone in the world

Have you ever thought–when you say, "I can't say fairer than that"–you just have?

Permalink Add your comment
Share post
Richard Walker

Cicada joke

Visible to anyone in the world

I didn’t get this one at first. Then it clicked.

Permalink Add your comment
Share post
Richard Walker

Dialogue

Visible to anyone in the world

“Can I use the dial please?”

“No! It’s mine all mine, bwahaha!”

Permalink 1 comment (latest comment by Jan Pinfield, Sunday, 15 Nov 2020, 10:52)
Share post
Richard Walker

Groaner

Visible to anyone in the world
Edited by Richard Walker, Saturday, 14 Nov 2020, 22:25

Q. What goes "99, 100, Phew!"

A. A centipede counting its legs.

Permalink Add your comment
Share post
Richard Walker

Round Table Puzzle

Visible to anyone in the world
Edited by Richard Walker, Saturday, 14 Nov 2020, 22:21



Permalink 3 comments (latest comment by David Tracey, Sunday, 15 Nov 2020, 16:55)
Share post
Richard Walker

Pademelon

Visible to anyone in the world
Edited by Richard Walker, Friday, 13 Nov 2020, 23:30

This intersting little animal is a pademelon, a kind of marsupial, related to kanaroos and wallabies.


I had never heard of pademelons, but the name came up in a quiz tonight. There are seven species but the Wikpepdia article is a bit sparse on detail.

Here's a video from of young pademelons playing.

Permalink Add your comment
Share post
Richard Walker

Cats on Cushions Puzzle

Visible to anyone in the world
Edited by Richard Walker, Friday, 13 Nov 2020, 02:15

This is a sawn-down version of a puzzle "Arranging cats and dogs" that Matt Parker recently posted on YouTube.

In our version we have a pair of cats, and eight cushions. We want to seat each cat on its own cushion, with the restriction that they cannot occupy adjacent cushions, in case they start a cat fight. Here is one possible arrangement.


You see the cats are not next to one another, so the rule is satisfied.

The question is: how many possible arrangements are there? What if there were 9 cushions? Or 10? Can you give a general formula?

Permalink 4 comments (latest comment by Richard Walker, Saturday, 14 Nov 2020, 21:09)
Share post
Richard Walker

Procrastination

Visible to anyone in the world

I’ve been asked to write a short piece on procrastination. But I can do it later.

Permalink Add your comment
Share post
Richard Walker

Ant Joke

Visible to anyone in the world

Q. How does an ant who’s not driving a taxi any longer feel?

A. Exuberant. 

Permalink Add your comment
Share post
Richard Walker

Tom Swifty

Visible to anyone in the world

“That ditch is swarming with some kind of insect”, said Tom trenchantly.

Permalink Add your comment
Share post
Richard Walker

A Ballad of Proverbs, after Villon

Visible to anyone in the world
Edited by Richard Walker, Wednesday, 11 Nov 2020, 03:52

A cat can look at a queen.

Cats have nine lives.

How many shopping days till Christmas?

Let sleeping dogs lie.

Every dog has his day.

How many shopping days till Christmas?

Too many cooks spoil the broth.

Many hands make light work.

How many shopping days till Christmas?

A bird in the hand is worth two in the Bush.

Birds of a feather flock together.

How many shopping days till Christmas?

It’s always darkest just before the dawn.

There’s light at the end of the tunnel.

How many shopping days till Christmas?

Don’t count your chickens before they are hatched.

Which came first, the chicken or the egg?

How many shopping days till Christmas?

Fools rush in where angels fear to tread.

Faint heart never won fair lady.

How many shopping days till Christmas?

Cut your coat according to your cloth.

A stitch in time saves nine.

How many shopping days till Christmas.

Beggars can’t be choosers.

If wishes were horses, beggars would ride.

How many shopping days till Christmas?
Permalink Add your comment
Share post
Richard Walker

Milongueo del Ayer, by Abel Fleury

Visible to anyone in the world
Edited by Richard Walker, Thursday, 12 Nov 2020, 11:59

This features my friend Mike Lloyd playing a duet, remotely of course, with Sebastian Pompilio, a professional guitarist and guitar teacher based in Argentina.

Mike says they did the duet with a lot of help from audio/video editing software, recording parts separately and then stitching them together.

Permalink Add your comment
Share post
Richard Walker

Supper 09/11/2030

Visible to anyone in the world
Edited by Richard Walker, Tuesday, 10 Nov 2020, 00:52


Permalink 1 comment (latest comment by Gill Burrell, Tuesday, 10 Nov 2020, 16:38)
Share post
Richard Walker

A Bottle Hits The Dust

Visible to anyone in the world
Edited by Richard Walker, Tuesday, 10 Nov 2020, 00:53

An old shelf collapsed today, sadly; a bottle of Port fell and broke. No use crying, but why is Port called Port?

It's named for Oporto which means 'The port' in Portugese. I knew that but wanted to dig deeper.

Portugal itself seems to have been named in Latin, Portus Cale, the first element meaning port or gate or mountain pass etc. in Latin, the second a Celtic name, of a deity, or a people, or lots of other possibilites, see

https://en.wikipedia.org/wiki/History_of_Portugal#Etymology

But what about Latin portus? What are its origins? I was surprised. It is conjecturered to stem from a word pertus = crossing in the long-ago origin of most (but not all!) European languages.

So, even more surprisingly perhaps, the English word ford has the same origin. Grimm's laws documented that words that began with 'p' or 'q' in Greek or Latim have mutated to start with 'f' in Germanic languages, so e.g.

pater (Latin) -> father

pisce (Latin) -> fish

pyre (Greek) -> fire

pente (Greek) -> five

quercus (Latin) -> fir (not the same tree, but the same word root)

pothi (Greek) -> foot

If you want to feed in anything more, you have an opportunity to do so in the Comments.


Permalink 2 comments (latest comment by Richard Walker, Tuesday, 10 Nov 2020, 22:15)
Share post

This blog might contain posts that are only visible to logged-in users, or where only logged-in users can comment. If you have an account on the system, please log in for full access.

Total visits to this blog: 2073489