By Michael Carroll
Best-selling author of If You Agree With Me, Then You're Right Too!

Introduction     Part 1     Part 2     Part 3     Part 4     Part 5

Science: What's it all about?

To some, even the mention of the word "science" conjures up images of white-coated, balding boffins with thick glasses who spend their time in a large stone-walled room filled with racks of test tubes and large electrical equipment with sparks that go up and – sometimes – down.

But science is more than just that... Science is the study of nature and the behaviour of the physical universe. It's nothing to be afraid of.

Throughout the course of this series, I'll be introducing you to some of the basic concepts of science, and extrapolating from there towards the conclusions that have helped to shape our world.

To begin, let's look at the most fundamental of all sciences: the conversion of energy.

Lesson one – Energy: What it is and what it's for

Everything in the universe contains energy in one form or another.

Take a rubber ball, for example. Now, hold that rubber ball in the palm of your outstretched hand. The ball now contains potential energy, because – potentially – you might drop it.

If you do drop that ball, its potential energy turns into kinetic energy. That is, it's still the same ball, but now it has the added property of moving downwards. When the ball hits the ground, what happens? It bounces, of course: the downward energy pushes the ball to the ground, then when the downward energy can't go any further, it transforms into upward energy.

"A-ha!" you might say, "Why, then, doesn't the ball bounce to the same height as I dropped it from?"

Well, that's because part of the downward energy is diverted into reflective energy that manifests in the form of sound waves – in other words, a "boing". So now there's less kinetic energy in the ball. Hence, each subsequent bounce gets smaller.

Scientists have shown that if you drop the ball in a vacuum, there is of course no sound, so the ball continues bouncing forever. In The Science Institute of Colorado, Texas, there is a vacuum chamber which has been home to a continually bouncing ball since 1982.

But outside of a vacuum, the ball will eventually come to rest, all of its energy having been transferred into "boings".

So what happens to these "boings"? Where do they go?

Well, small bits of them go into your ears, which cause the eardrums to vibrate off the tiny little hammers and anvils and stamens and pistils inside your ear canal, which in turn sends signals to your brain to let you know that there was a "boing".

But that's not the whole story: you see, sound waves cause the air to move (much like sea waves create the tides and enable water to flow down rivers). The moving of the air is of course known as wind. You might think that wind is simply the air moving from one place to another, and, well, it is, but it can do interesting things along the way.

Air might seem insubstantial – you can't touch it, taste it, see it or hear it. Okay, you can hear it, but that's just the wind pushing against the windows, which vibrate and cause more sound waves inside the house, which in turn go into your ear and so on. But that's not the point: the point is that air is not insubstantial – it has mass and density and pressure and humidity, all the attributes we associate with things that are substantial. I mean, just ask any parachutist! After all, if it wasn't for the pressure of the air, most of them would land on target most of the time.

But wind can also be useful: it can be channeled into turning the sails on a windmill, for example. This can be used to power substations that make electricity from coal. The exact methods for converting rotatative energy into electrivical energy will be covered in a later chapter, but for now, it's important to note that if it wasn't for ball games, we'd have less wind and probably less electricity.

Now, here's where it gets tricky: Science has shown us that we can drop things that don't bounce!

Say you drop an egg instead of a rubber ball. A fresh egg, not a hard-boiled one. If you drop this egg onto concrete and not a thick carpet, the egg will break.

There are several questions you might ask at this point: "Why does this happen? What's happened to the downward energy? Where's the boing? Does that mean the lights will go out?"

An egg breaks because it does not have what you could call "bouncability". That is, the shell of the egg is not resilient enough to convert the downwards energy into upwards energy: the shell breaks under the pressure. But the energy doesn't just go nowhere: there's no "boing!" but there is what's commonly referred to as a "splat!" Now, strictly speaking there is no "splat" at this point: there is a "crack"... This is the sound wave caused by the breaking of the eggshell: the rest of the energy is converted into sidewards energy, resulting in bits of egg and shell spreading out in all horizontal directions.

"A-ha!" You might say again. "So, where does the energy go then?"

A good question, but simply answered: the sidewards energy moves the bits of egg out horizontally, but these bits are subject to "gravity" (coming up in a later chapter), which converts the sidewards energy back into downwards energy. When the bits hit the ground again, it is then that they make the "splat".

Before I wrap up this chapter, allow me to give you another example of how energy conversion works...

A man is driving his car home from work.

A simple enough situation, and probably quite common. Now, how does this car move? From where does it get its forward energy?

Well, millions of years ago the sun (I'll be getting into astronomical energy in a later chapter) turned some of its energy into sunlight. Plants on Earth converted this light into plant energy, which enabled them to grow and reproduce. In time, dinosaurs ate the plants – converting vegetable energy into animal energy – and then the dinosaurs died. But when they died, their energy didn't just disappear: it hung around and after a long time turned their bodies into oil. From this, we get petroleum (or gasoline, in American). This is burned inside a car in lots of little explosions. When something explodes, it gets turned into a gaseous state very rapidly, and the gas expands with some force. As we know from the above lesson on air pressure, we can use expanding (or moving) gas to make things turn around, like the drive shaft inside a car.

So, next time you meet an environmentalist who complains that you should be driving a solar-powered vehicle, all you have to do is grin and explain that you already are!