The definations wanted by you are given below-
In physics, matter is commonly defined as the substance of which physical objects are composed, not counting the contribution of various energy or force-fields, which are not usually considered to be matter per se (though they may contribute to the mass of objects). Matter constitutes much of the observable universe, although again, light is not ordinarily considered matter. Unfortunately, for scientific purposes, "matter" is somewhat loosely defined.
Mass is a property of a physical object that quantifies the amount of matter and energy it is equivalent to. Mass is a central concept of classical mechanics and related subjects, and there are several forms of mass within the framework of relativistic kinematics (see mass in special relativity and mass in General Relativity). In the theory of relativity, the quantity invariant mass, which in concept is close to the classical idea of mass, does not vary between single observers in different reference frames.
An elementary particle is a particle with no measurable internal structure, that is, it is not a composite of other particles. They are the fundamental objects of quantum field theory. Elementary particles can be classified according to their spin, with fermions having half-integer spin and bosons integer spin.
Space has been an interest for philosophers and scientists for much of human history. The term is used somewhat differently in different fields of study, hence it is difficult to provide an uncontroversial and clear definition outside of specific defined contexts. Disagreement also exists on whether space itself can be measured or is part of the measuring system. (See Space in philosophy.) Many fields use an operational definition in which the units of measurement are defined, but not space itself.
In chemistry and physics, an atom (Greek átomos meaning "indivisible") is the smallest particle of a chemical element that retains its chemical properties.
A chemical element, often called simply an element, is a substance that cannot be decomposed or transformed into other chemical substances by ordinary chemical processes. All matter consists of these elements and as of 2006, 117 unique elements have been discovered or artificially created. The smallest particle of such an element is an atom, which consists of electrons centered about a nucleus of protons and neutrons.
In chemistry, a molecule is an aggregate of two or more atoms in a definite arrangement held together by chemical bonds. Chemical substances are not infinitely divisible into smaller fractions of the same substance: a molecule is generally considered the smallest particle of a pure substance that still retains its composition and chemical properties. Certain pure substances (e.g., metals, molten salts, crystals, etc.) are best understood as being composed of networks or aggregates of atoms or ions instead of molecular units.
In particle physics, antimatter extends the concept of the antiparticle to matter, wherein if a particle and its antiparticle come into contact with each other, the two annihilate —that is, they may both be converted into other particles with equal energy in accordance with Einstein's equation E = mc2. This gives rise to high-energy photons (gamma rays) or other particle–antiparticle pairs-.
2006-11-28 16:02:48
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answer #1
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answered by Anonymous
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Yes. And if you're taking a 1'st year Physics class, you should be getting them. They are the basic definitions of mass, length, and time. Everything else is defined in those terms.
Doug
2006-11-27 01:31:48
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answer #2
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answered by doug_donaghue 7
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