What is Physics

Physics, a branch of science, is traditionally defined as the study of
matter, energy, and the relation between them. The interaction between matter
and energy is found everywhere. In order for matter to move, it requires some
form of energy.
Sports show many good examples of the relationship between matter and energy.
For instance, a pitcher requires energy to throw a baseball at the incredible speed
and accuracy that is needed to keep the batter from using his energy to try and hit
the ball. The batter exhibits the need for a certain trajectory because he/she needs
to hit the ball hard enough and keep it high enough to sail over the outfield wall.
On the other hand, the batter must be certain to keep the trajectory low enough so
that the ball will reach the fence. Trajectory is also seen in basketball, where
players must shoot the ball with enough arch to get over the front of the rim, and go
through the hoop. The energy required to do this comes from not only the arms, but
the legs as well.
The medical field has seen enormous breakthroughs because of principles of physics.
Doctors are now able to use lasers for surgery. Lasers are based on the physical principle
of light, and are devices for the creation and amplification of a narrow, intense beam of
coherent light. New laser microsurgery can actually alter the shape of the cornea in the
eye so the patient's eyesight can return to normal, and he/she will no longer need those
bothersome glasses. Ultrasound is used in the medical field for destroying various unwanted
substances in the body such as kidney stones. Ultrasound uses sound waves to dissolve these
foreign bodies. If not for physics, ultrasounds would never have been discovered and utilized.
MRI scans, another new discovery, are able to show a complete three dimensional picture of the
interior structure of the body, and are extremely valuable in hospitals. These scans are based
on the principles of electromagnetism, and the phenomenon that nuclei of some atoms line up in
the presence of an electromagnetic field.
Understanding the dark matter of the universe, which has remained a mystery for quite some time,
is based primarily on theories of physics. We have yet to see a black hole, but physics has
explained what one is, and why we cannot see it. Otherwise we would have never known that it is
an extremely small region of space-time with a gravitational field so intense that nothing can
escape, not even light. Physics help to understand the dark matter of the universe, because it
applies theories to what the dark matter is. We are also able to look at distant spots in the
universe with new telescopes because of the principles of magnification and amplification of light.
Not only can physics better your baseball game and explain the dark matter of the universe,
but it can save lives. It remains a very important part of us and our world.