# The IntMath Newsletter - 19 May 2008

By Murray Bourne, 19 May 2008

1. New in Interactive Mathematics - Vectors
2. Math tips - (a) Temperatures; (b) Exam fear
3. Latest IntMath Poll
4. RSS feeds for the Math Blog
5. From the math blog
6. Money and happiness

## 1. New Vectors chapter in Interactive Mathematics

A lot of readers have asked me to write a chapter on vectors, so recently I did so. And it starts here, at Introduction to Vectors.

Vectors are a very important concept in mathematics and there are many real-life applications.

## 2. Math Tips - (a) Temperatures; (b) Exam fear

(a) Temperatures

We all know that the temperature of a substance is an indication of the amount of energy contained by the particles in a substance. More energy means higher temperature.

What if there is no energy in the substance and the particles don't move at all? Such a thing is almost possible, and it occurs at absolute zero. Absolute zero is written 0 K (the K stands for "kelvins" - notice there is no degrees sign), which is equivalent to −273.15°C. Scientists have managed to cool substances down to very close to 0 K.

Did you know that the first refrigerators were called "ice chests" and used blocks of ice cut from Canadian lakes? These ice blocks were shipped all over the world and because the ice melted slowly, there was still enough left to sell when they eventually got to places in the tropics. This multi-million dollar ice business collapsed when people started to use electric refrigerators in the 1920s.

The highest temperature ever recorded on Earth was 58°C (in Libya - northern Africa) and the lowest ever was −89° in Antarctica (near the South Pole). Fortunately for us, the mean (average) surface temperature of the Earth is around 14°C, made up of 8.5°C for land and 16°C for the sea. (Data for 1901 to 2000, source: NOAA.)

You have no doubt heard that since 2000, the global mean temperature has been around 0.5°C hotter than the mean for the whole 20th century.

For those of you who are still using the Fahrenheit scale, you can find the Centigrade equivalent using:

C = 5/9(F − 32)

So for example, human body temperature in Fahrenheit is 98°F. Converting to Centigrade, this is:

C = 5/9(98 − 32) = 5/9(66) = 36.7°C.

The German scientist Daniel Fahrenheit invented the first mercury thermometer in the early 1700s and proposed his weird Fahrenheit scale in 1724. The US is the only country still hanging on to this outdated temperature system.

(b) Exam Fear

Examination stress is a common condition suffered by students all over the world.

I have a simple law about stress, and it goes like this:

90% of our stress is self-inflicted.

Why do I say that? Let's look at some common student stresses:

My assignment is due tomorrow and I haven't even started it yet. And it looks so hard. And how long ago was this student given the assignment questions? Did he write it into his study diary and then begin the assignment on the night he was given it? Did he procrastinate until it was just too late? Did he increase his own stress?

I have a test tomorrow and I don't know anything. Test preparation should start before the lessons even start. It is good to read over what the lesson is about before the lesson so you have your questions ready. If you get into this habit, then the final preparation for a test is much, much easier. Also, good organisation via a study diary is a good way to reduce test stress.

I can't concentrate because I'm really sleepy. Sleep is vital for learning. We actually do our best problem solving and long-term learning while asleep. Many teenagers have terrible sleeping habits and then wonder why they walk around like zombies all day, having difficulty concentrating and learning new things.

Talking about fear, the Dalai Lama said:

If you have some fear of pain or suffering, you should examine whether there is anything you can do about it. If you can, there is no need to worry about it. If you cannot, then there is also no need to worry.

It boils down to what I call the Nike approach. If you can do something about it, just do it. If you can do your assignment, or study for that exam, just do it! If you can't, then do something about it. Ask questions. Read over the notes. Read similar textbooks to your own.

When it comes to things outside your control, then move on with your life, and don't become absorbed in your own worry.

## 3. Latest IntMath Poll

This month's IntMath poll asked readers about their favorite subject at school. I was impressed that 40% of you indicated that mathematics is (or was) your favorite subject.

40% Math
29% English
16% Science
7%  Music
6%  History
2%  Geography

I have to say that I am disappointed that Geography scored so low. As the Earth gets flushed down the environmental tube, we are going to need every geographer we can get to fix the mess.

The latest poll asks you about what causes you stress in school. You can vote on any page in Interactive Mathematics.

## 4. RSS Feeds for the Math Blog

Do you use a blog reader?

Instead of repeatedly visiting squareCircleZ (or any blog) to see if a new article has appeared, you can get an automatic notification using several different methods.

The easiest is to use an email notification, provided by Feedblitz. You can sign up on any page in the Math Blog by entering your email.

Another easy option is to see RSS feeds in your browser. Both Firefox and IE7 let you pull blog feeds directly into your browser. See how to do it in Firefox.

Once you start using RSS feeds you'll wonder how you lived without them.

## 5. From the math blog

1) Athens
Greece had a large influence on Western thought and methods of governance. Here are some recollections from my recent visit to Athens.

2) Vectors
There's a lot more to vectors than just forces and velocities. Check out this overview of the new Vectors chapter in Interactive Mathematics.

## 6. Money and happiness

And to finish this edition of the IntMath Newsletter, I'd like to leave you with this quote from Arnold Schwarzenegger on wealth and happiness:

Money doesn't make you happy. I now have $50 million, but I was just as happy when I had$48 million.

Have a good week 🙂

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