Game Development Reference
In-Depth Information
CHAPTER 9
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Boats and Things That Float
S
o far in this topic we've focused on land-based activities. It's time to hit the water. In this
chapter, we will explore the basic physics behind boats and things that float. As with the chapters
on sports and car simulations, we'll start armed with an understanding of Newtonian mechanics
and kinematics. The concepts of force, acceleration, torque, and velocity apply just as well to
boats as they do to projectiles or cars. The big difference with boats, of course, is that they float,
so we will learn about a new force that allows this to happen.
The emphasis of this chapter will be on powerboats, but an introduction will be provided
on the more complicated physics of sailboats. At the end of the chapter, the physics of surfing
will be explored. Some of the specific topics this chapter will cover include the following:
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A review of some basic nautical terminology
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Different boat hull types and what they are used for
•
The basic forces that act on a boat
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The force of buoyancy, what it is and how it is modeled
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How the power from a boat engine is converted into thrust to propel the boat
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The different drag forces that act on a boat
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How to obtain an acceleration profile for a boat or other watercraft from performance
test data
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An introduction to jet skis
Some Nautical Terminology
People have been sailing and floating on boats for thousands of years, and over time seafarers
have developed a rather unique terminology for describing the various components of a boat
and many other things besides. Before we get into details on how a boat moves through the
water, let's spend a little time going over some basic terminology.
The first things to discuss are the words “boat” and “ship.” They are both generic terms for
a vessel that travels on the water. The word “boat” is generally used for smaller vessels, whereas
“ship” is generally used to describe larger, seagoing vessels. One commonly used distinction is
that a boat is a vessel that can be carried aboard a ship. The focus of this chapter will be on
powerboats and speedboats, so the term “boat” will be used throughout.
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