Scientific disciplines use a process whereby information is gathered
through repeated experiments, evaluation, and review by professional scientists.
This information, in the form of laws and theories, is shared with the scientific
community through publications. Non-scientific disciplines generally do not
use regimented experimentation; instead, they use observation, facts already
in existence, and supposition.
A hypothesis is a logical statement that explains an event or answers
a question. It is important to scientific thinking because it must be testable
— the scientist must be able to support it or disprove it.
Sometimes the results from a one-time experiment are inconclusive —
they neither support nor disprove the hypothesis. A new experiment must be
conducted or more information collected. Repeatability is the process whereby
scientists eliminate bias and test their results by having independent investigators
repeat the experiment. If a hypothesis is supported by many experiments and
several different investigators, it is considered reliable.
The scientific method is the process of gathering information and generally
involves observation, hypothesis formation, hypothesis testing, critical evaluation
of results, and the publishing of findings.
The second law of thermodynamics states that when energy is converted
from one form to another, there is a loss of useful energy. This loss is a
form of pollution. An example would be the emissions from power plants.
See figure 4.2.
The atoms in a molecule are held together by chemical bonds which result
from the interaction of the electrons. During a reaction, electronic attractions
are rearranged, and bonds between the atoms are either broken or new ones
formed.
The first law of thermodynamics states that energy can be neither created
nor destroyed. The second law states that when energy is transformed from
one form to another there is a loss of useful energy.
In solids, molecules have a low amount of energy and vibrate close
to one another. In liquids, higher-energy molecules are farther apart and
flow over each other. In gases, the molecules move rapidly and are far apart.
Five kinds of energy are heat, light, electricity, chemical energy,
potential, and kinetic energy.
Different energy forms are of different quality. Electrical energy
is of high quality and can be easily transformed to perform a variety of useful
actions. Heat in ocean water is of low quality because of the small temperature
difference between the ocean in its surroundings. It can do little work for
us.
