Simple Physics

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Don't get scared, this ain't hard.

Please, totally disregard the blue square below, because we are not going to use it anyway. It is just here to show you the kind of stuff we are not going to talk about. You and I have no interest in blowing up cities.

Click to see where I stole this.
 

Otherwise, there are a few simple concepts of basic classical physics which make the entire world (...hell, the entire universe) easy to understand and predict.

Classical physics is the stuff about how things move around you, without all the math and gibberish like the blue square above.

You know, stuff like: you drop a ball, and it bounces off the floor, and it always will bounce off the floor—and exactly the same way if you drop it the same way.

Therefore, if you drop the ball from a specific height, it will always bounce back just exactly an exact specific height, exactly the same way every time.

Guaranteed!

Throw it just so, and swish... through the hoop.

You know, stuff like that.

If you never learn the most basic literal facts about how objects in the real world behave, you leave yourself open to an incredible amount of deceit foisted on you by purveyors of magic, myth, and expensive bicycles.

Stuff like, "Oh, look, there's a quarter behind your ear..." or, "They don't look and talk like you do, therefore they are total fucking evil bastards, rotten to the core. They are coming after you, and they deserve to die," or, "You really need this little doohickey on your bicycle in order to go fast. It is expensive, but you are worth it. You want to win, don't you?"

Stuff like that.

Otherwise, if you are familiar with the following concepts the world is your oyster... especially if it is the world of cycling.

Knowing these things can help you beat just about anybody who doesn't know them.

Here is the first thing you should know.

inertia - means that things tend to stay just exactly the way they are, either in motion or at rest. An outside force of some sort is required to change either situation.

If something is not moving, it takes force to move it. On the other hand, if something is moving, it takes force to stop it, and it takes exactly the same amount of force to stop it as it did to start it.

Think about that for awhile, look at the things around you, and guess what all this means for you on your bicycle.

Here are two things it means (I did not make this up):

1) If you get your bicycle moving, it doesn't want to stop. Not only does it not want to stop, it doesn't even want to slow down... at all. Something has to happen to make it slow down and stop.

Doesn't that make you happy? If you get your bicycle going at 23 miles an hour, it will stay going that way forever. All you have to do is avoid the things that would make it slow down and stop (such as brick walls), and it is just exactly as hard to make it slow down and stop as it was to get it going in the first place.

The thought of that gets me pretty excited, except for the part about the brick wall.

2) On the other hand, if your bicycle is not moving, it doesn't want to start moving. Not only does it not want to get going fast, it doesn't want to get going at all. In fact, it takes just as much force to get it going only a little bit faster as it does to get it going to the speed of light.

Doesn't that make you happy? You don't need any more effort to get your bicycle going really fast than you do to just get it going at all. The thought of that also gets me pretty excited.

You can get your bike going, can't you? Then you can get going as fast as there is. There are a couple minor problems, but you can deal with them.

Here's a little math problem. It is just addition, subtraction, and division stuff, so not hard in the least. Besides I am giving you the answer right after the question, so at least try it:

Question: Discounting air and friction (hills don't matter at all), if you are on your bike going 20 mph, and your speed is increasing the smallest amount possible, let's call it spinning 100 watts, how many more watts will you need to reach 23 mph?

Answer: None.

You can think about that for awhile if you like, but it is absolutely true, so I am moving on to something else.

Oh, I almost forgot. You might be wondering what force is.

force: Force is pow, pop, bang, zingo, and that about covers it as good as anybody ever has.

Remember, I said there are a couple minor problems to deal with, and the first problem is that the air likes to keep you from going really, really fast.

Actually, the air likes to hold you back harder and harder, the faster and faster you go.

 The math word for that is logarithmic, or maybe somewhat parabolic, but I promised there would be no gibberish here, so forget those words.

Just remember this: the harder you push air, the more pissed off it gets and pushes back harder the more harder you pushed it back first.

No, that was not a misprint. Read it again more slowly.

Below is a picture that shows you how the air likes to make it harder for you to go faster, and how the harder you go harder the more harder it likes to make it more harder for you to go faster.

Once again, that was not a misprint. You will just have to accept the slight error in grammar immediately above, because like I said, there is a mathematical term for what it describes (logarithmic), but you don't need to know it and should try to forget it as soon as you can. If you use a word like that, people will think you know something, and they won't let you go on a ride with them.

However, you might like to be aware this stuff (inertia, force, air resistance) works out best for you on a more or less circular route beginning and ending in the same place—which also takes care of the hills.

Ok, here's the chart:

 Did you notice there is a little target on it for the Widder to think about?

See the numbers going up the left side?

Those are the numbers from your power meter (watts). All you have to do is get your meter showing those numbers, and the numbers across the bottom (speed) will take care of themselves.

This book is not called Cycling Performance Simplified for nothing.

The bend in the line on the graph shows just how hard the air likes to push back on you depending on how hard you are trying to push on it.

If you don't like math, you can have your numbers worked out for you by my calculator which tracks well with the chart above based on your putting in only your watts and weight. It also calculates your Race Category and is called the Super Simple Power to Weight Calculator.

Hills have no effect. They just go up and down exactly like the bouncing ball described above, so there is a chapter about how there are no hills.

There is also a chapter about how there is no wind, because there is way, way, way too much air for you to worry about wind.

Got it? Good.

See? That wasn't hard... weird maybe, but not hard.

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