Flows, Cycles, and Conservation Students observe objects may break into smaller pieces, be put together into larger pieces, or change shapes. Students learn matter is made of particles and energy can be transferred in various ways and between objects. Students observe the conservation of matter by tracking matter flows and cycles before and after processes and recognizing the total weight of substances does not change. Students learn matter is conserved because atoms are conserved in physical and chemical processes.
The next concept—scale, proportion, and quantity—concerns the sizes of things and the mathematical relationships among disparate elements.
The next four concepts—systems and system models, energy and matter flows, structure and function, and stability and change—are interrelated in that the first is illuminated by the other three.
Each concept also stands alone as one that occurs in virtually all areas of science and is an important consideration for engineered systems as well. Regardless of the labels or organizational schemes used in these documents, all of them stress that it is important for students to come to recognize the concepts common to so many areas of science and engineering.
Patterns Patterns exist everywhere—in regularly occurring shapes or structures and in repeating events and relationships. For example, patterns are discernible in the symmetry of flowers and snowflakes, the cycling of the seasons, and the repeated base pairs of DNA.
Noticing patterns is often a first step to organizing and asking scientific questions about why and how the patterns occur. One major use of pattern recognition is in classification, which depends on careful observation of similarities and differences; objects can be classified into groups on the basis of similarities of visible or microscopic features or on the basis of similarities of function.
Such classification is useful in codifying relationships and organizing a multitude of objects or processes into a limited number of groups.
Patterns of similarity and difference and the resulting classifications may change, depending on the scale at which a phenomenon is being observed. For example, isotopes of a given element are different—they contain different numbers of neutrons—but from the perspective of chemistry they can be classified as equivalent because they have identical patterns of chemical interaction.
Once patterns and variations have been noted, they lead to questions; Page 86 Share Cite Suggested Citation: A Framework for K Science Education: Practices, Crosscutting Concepts, and Core Ideas.
The National Academies Press. Engineers often look for and analyze patterns, too. For example, they may diagnose patterns of failure of a designed system under test in order to improve the design, or they may analyze patterns of daily and seasonal use of power to design a system that can meet the fluctuating needs.
The ways in which data are represented can facilitate pattern recognition and lead to the development of a mathematical representation, which can then be used as a tool in seeking an underlying explanation for what causes the pattern to occur.
For example, biologists studying changes in population abundance of several different species in an ecosystem can notice the correlations between increases and decreases for different species by plotting all of them on the same graph and can eventually find a mathematical expression of the interdependences and food-web relationships that cause these patterns.
Progression Human beings are good at recognizing patterns; indeed, young children begin to recognize patterns in their own lives well before coming to school. They observe, for example, that the sun and the moon follow different patterns of appearance in the sky. Once they are students, it is important for them to develop ways to recognize, classify, and record patterns in the phenomena they observe.A Guest post by: Dr.
Minqi Li, Professor Department of Economics, University of Utah E-mail: [email protected] This Annual Report evaluates the future development of world energy supply and its impact on the global economy as well as climate change. News Dive into the world of science!
Read these stories and narratives to learn about news items, hot topics, expeditions underway, and much more.
Where there is a plentiful head of water it can be made to generate compressed air directly without moving parts.
In these designs, a falling column of water is purposely mixed with air bubbles generated through turbulence or a venturi pressure reducer at the high-level intake. Terminology in fluid dynamics. The concept of pressure is central to the study of both fluid statics and fluid dynamics.
A pressure can be identified for every point in a body of fluid, regardless of whether the fluid is in motion or not. Pressure can be measured using an aneroid, Bourdon tube, mercury column, or various other methods.
The law of conservation of energy can be used also in the analysis of flowing fluids. The Bernoulli’s equation can be considered to be a statement of the conservation of energy principle Bernoulli’s Principle.
It puts into a relation pressure and velocity in an inviscid incompressible flow. The general energy equation is simplified to.
May 05, · The conservation of energy is a fundamental concept of physics along with the conservation of mass and the conservation of momentum.
Within some problem domain, the amount of energy remains constant and energy is .