Are astronauts actually weightless?

Astronauts in orbit are still strongly attracted to the Earth by gravity. So why do they float about as if they were in deep space, far from any big masses?

Here is a nice simple blog post which gets across the basics. For a more general/detailed explanation…I have tutorial sheets available!

Equations are important

From Ian Stewart’s latest book about equations

The origin of equations

The ancient Babylonians and Greeks knew about equations, though they wrote them using words and pictures. For the past 500 years, mathematicians and scientists have used symbols, the crucial one being the equals sign. Unusually, we know who invented it, and why. It was Robert Recorde, who in 1557 wrote in his treatise The Whetstone of Witte: “To avoide the tediouse repetition of these woordes: is equalle to: I will sette as I doe often in woorke use, a paire of paralleles, or gemowe lines of one lengthe: bicause noe .2. thynges, can be moare equalle.”

Maths in Scotland

It seems that some aspects of the various Mathematics curricula in Scotland are working well in comparison with the English system.  There is still a long way to go to make Maths as popular and well taught as it is, for example, in Finland.

Why some people dislike maths

It’s not surprising that some people learn to hate maths.

Here is  an article which talks about how poor teaching can sometimes cause ongoing problems. It’s just not fair that artistic people are frequently denied good explanations of mathematical concepts.

Agent-based simulations -StarLogo

If you fancy making some simulations of lots of interacting software agents, this is a great place to start playing about with large numbers of ‘turtles’.

StarLogo even includes a graphical programming interface.

Central limit theorem

The central limit theorem is pretty cool and is outlined here.

So
toss a coin 100 times
count 1 for each head and 0 for each tail
add these numbers up ->sum

now repeat all of the above say 200 times

the 200 sum values will be distributed normally

eg
Sum/ Number of occurrences
2 /…3
10 /…..5
15 /……..8
23 /…………12
32 /……………………23
41 /……………………………..35
52 /…………………………………………….50
65 /………………………..29
73 /……………15
75 /……….10
82 /….4
93 /….4
95 /.1
100 /.1