Vectors aren’t restricted to two dimensions either. They can be any size
at all. You would use a 3D vector, (x, y, z) for example, to represent the
velocity of a vehicle that moves in three dimensions, like a helicopter.
Let’s take a look at some of the things you can do with vectors.
Adding and Subtracting Vectors
Imagine you are a contestant in a TV reality game. You are standing in a
clearing in the jungle. Several other competitors stand beside you. You’re
all very nervous and excited because the winner gets to date Cameron
Diaz… and the losers have to watch. Sweat is dripping from your forehead,
your hands are clammy, and you cast nervous glances at the other competi
tors. The bronzed, anvil-chinned TV host steps forward and hands a gold-
trimmed envelope to each competitor. He steps back and orders you all to
rip open your envelopes. The first person to complete the instructions will
be the winner. You frantically tear away at the paper. Inside is a note. It
I’m waiting for you in a secret location. Please hurry, it’s very hot in
here. You can reach the location by following the vectors (–5, 5), (0,
–10), (13, 7), (–4, 3).
With a smile on your face you watch the rest of the competitors sprint off
in the direction of the first vector. You do a few calculations on the back of
the envelope and then set off in a completely different direction at a lei-
surely stroll. By the time the other competitors reach Cameron’s hideout,
sweating like old cheese and gasping for breath, they can hear your playful
giggles and the splash of cool shower water…
You beat the opposition because you knew how to add vectors together.
Figure 1.17 shows the route all the other competitors took by following the
vectors given in Cameron’s note.
A Math and Physics Primer | 19
Figure 1.17. The route of the opposition