Figure 5 Panels on a solar car convert energy from the sun into the mechanical energy of its moving parts.
Energy
Energy exists in many forms. Moving objects have a kind of energy called kinetic energy. Objects moved against a force have another kind of energy called potential energy. Energy also exists in matter itself. When one form of matter changes into another form, energy is either absorbed or released. Matter itself can also be changed into energy.
Energy can be transferred from one form or object to another, but it can never be destroyed. If you push on a door and it swings open, you transfer energy from yourself to the door. Your cells are using the chemical energy stored in the food you have eaten to supply energy to your muscles, which then transfer energy to the door.
Science and Your Perspective
As you read this book, remember that science is both a process and a body of knowledge. The information in this book represents the best up-to-date models of how the universe works. However, like all models, some of these models will be rejected and replaced in the future. For instance, more moons revolving around Jupiter and Saturn will most likely be discovered as telescopes get better. It is therefore possible that by the time you read this book Saturn will be known to have more than the 62 moons currently identified. Be skeptical. Ask questions. Be aware that the scientific facts of today might change tomorrow. However, believe in the scientific process that has discovered them. And believe that you may be the one who makes the discoveries that will change scientific facts in the future.
Section 1.1 Assessment
Reviewing Concepts
How does the scientific process start and end?- How are science and technology related?
- What are the branches of natural science?
Explain the advantages and disadvantages of subdividing science into many different areas.
Why do scientists seek to discover new laws of the universe?
Critical Thinking
Evaluating Why does the progress of science require both curiosity and methodology? Explain the role of each in scientific investigations.
Making Judgments Advances in science do not always immediately lead to advances in technology. Why are such scientific advances still valuable?
Classifying Is the study of the muscle movements in the human body an example of biology or of physics? Explain.
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