31
Introducing Physics
Physics at the Movies
The laser cannons in
Star Wars
—supposedly focused beams of
light—would move through space so fast there would be no way a
person’s eye could detect their motion at close range, unless the
beam was left on for a long period of time and fired through a cloud
of dust. Of course, the visual effect is important to the success of
the movie, so go ahead and suspend reality for the films.
them, gaining speed as they go (rather than shooting off to one side or the
other). It has always been this way because physics is part of the natural
world.
The Science of Motion
Look around. Everywhere you look things are in motion. Pay attention to
the way the objects move, and you will notice these motions are usually
predictable. This fact is true everywhere in the world. Sir Isaac Newton
noticed it and authored his famous Laws of Motion after long hours of ob-
serving and testing the patterns of objects in motion. Newton’s laws have
become important to many aspects of life—from world travel to personal
comforts in our homes.
Newton’s laws provide the basis for many discoveries and technological
advances we often take for granted. Airplanes fly because the lift created
