Definitions of Energy
A given object possesses more energy of motion when it is moving faster.
Energy can be transferred by moving objects or by sound, light, heat, or electric currents.
Conservation of Energy and Energy Transfer
Energy is present whenever there are moving objects, sound, light, or heat. When objects collide, energy can be transferred from one object to another, thereby changing their motion. In such collisions, some energy is typically also transferred to the surrounding air; as a result, the air gets heated and sound is produced.
Energy can also be transferred by electric currents, which can then be used locally to produce motion, sound, heat, or light. The currents may have been produced to begin with by transforming the energy of motion into electrical energy.
Relationship Between Energy and Forces
When objects collide, the contact forces transfer energy so as to change the objects’ motions.
Energy in Chemical Processes and Everyday Life
The expression “produce energy” typically refers to the conversion of stored energy into a desired form for practical use.
Natural Resources
Energy and fuels that humans use are derived from natural sources, and their use affects the environment in multiple ways. Some resources are renewable over time, and others are not.
Defining Engineering Problems
Possible solutions to a problem are limited by available materials and resources (constraints). The success of a designed solution is determined by considering the desired features of a solution (criteria). Different proposals for solutions can be compared on the basis of how well each one meets the specified criteria for success or how well each takes the constraints into account.
Wave Properties
Waves, which are regular patterns of motion, can be made in water by disturbing the surface. When waves move across the surface of deep water, the water goes up and down in place; there is no net motion in the direction of the wave except when the water meets a beach.
Waves of the same type can differ in amplitude (height of the wave) and wavelength (spacing between wave peaks).
Information Technologies and Instrumentation
Digitized information can be transmitted over long distances without significant degradation. High-tech devices, such as computers or cell phones, can receive and decode information—convert it from digitized form to voice— and vice versa.
Optimizing The Design Solution
Different solutions need to be tested in order to determine which of them best solves the problem, given the criteria and the constraints.
Electromagnetic Radiation
An object can be seen when light reflected from its surface enters the eyes.
Structure and Function
Plants and animals have both internal and external structures that serve various functions in growth, survival, behavior, and reproduction.
Information Processing
Different sense receptors are specialized for particular kinds of information, which may be then processed by the animal’s brain. Animals are able to use their perceptions and memories to guide their actions.
The History of Planet Earth
Local, regional, and global patterns of rock formations reveal changes over time due to earth forces, such as earthquakes. The presence and location of certain fossil types indicate the order in which rock layers were formed.
Earth Materials and Systems
Rainfall helps to shape the land and affects the types of living things found in a region. Water, ice, wind, living organisms, and gravity break rocks, soils, and sediments into smaller particles and move them around.
Plate Tectonics and Large-Scale System Interactions
The locations of mountain ranges, deep ocean trenches, ocean floor structures, earthquakes, and volcanoes occur in patterns. Most earthquakes and volcanoes occur in bands that are often along the boundaries between continents and oceans. Major mountain chains form inside continents or near their edges. Maps can help locate the different land and water features areas of Earth.
Biogeology
Living things affect the physical characteristics of their regions.
Natural Hazards
A variety of hazards result from natural processes (e.g., earthquakes, tsunamis, volcanic eruptions). Humans cannot eliminate the hazards but can take steps to reduce their impacts.
Designing Solutions to Engineering Problems
Testing a solution involves investigating how well it performs under a range of likely conditions.
Defining and Delimiting Engineering Problems
Possible solutions to a problem are limited by available materials and resources (constraints). The success of a designed solution is determined by considering the desired features of a solution (criteria). Different proposals for solutions can be compared on the basis of how well each one meets the specified criteria for success or how well each takes the constraints into account.
Developing Possible Solutions
Research on a problem should be carried out before beginning to design a solution. Testing a solution involves investigating how well it performs under a range of likely conditions.
At whatever stage, communicating with peers about proposed solutions is an important part of the design process, and shared ideas can lead to improved designs.
Tests are often designed to identify failure points or difficulties, which suggest the elements of the design that need to be improved.
Optimizing the Design Solution
Different solutions need to be tested in order to determine which of them best solves the problem, given the criteria and the constraints.