5 presidentes los ultimos 5 años
Answer:
Visible Light Absorption
Atoms and molecules contain electrons. It is often useful to think of these electrons as being attached to the atoms by springs. The electrons and their attached springs have a tendency to vibrate at specific frequencies. Similar to a tuning fork or even a musical instrument, the electrons of atoms have a natural frequency at which they tend to vibrate. When a light wave with that same natural frequency impinges upon an atom, then the electrons of that atom will be set into vibrational motion. (This is merely another example of the resonance principle introduced in Unit 11 of The Physics Classroom Tutorial.) If a light wave of a given frequency strikes a material with electrons having the same vibrational frequencies, then those electrons will absorb the energy of the light wave and transform it into vibrational motion. During its vibration, the electrons interact with neighboring atoms in such a manner as to convert its vibrational energy into thermal energy. Subsequently, the light wave with that given frequency is absorbed by the object, never again to be released in the form of light. So the selective absorption of light by a particular material occurs because the selected frequency of the light wave matches the frequency at which electrons in the atoms of that material vibrate. Since different atoms and molecules have different natural frequencies of vibration, they will selectively absorb different frequencies of visible light.
Oxygen and glucose at top
carbon dioxide and water at bottom
Answer:
The economic concept of scarcity.
Explanation:
In economics, <em>scarcity</em><em> </em>represents the phenomenon of <em>limitless</em> <em>wants</em> suppressed by <em>limited</em><em> </em><em>resources</em>.
In this case, Allie feels she needs $90 shoes while she has not got the resources required to buy them.
This typical economic problem can be solved by moderating one's wants and clearly identifying what is priority from what is not, then intelligently making decisions on what available resources should be spent.
When capsaicin – the chemical in spicy foods that makes them so hot, Hot, HOT – hits your tongue, your body registers the sensation as pain. This in turn triggers the release of endorphins, otherwise known as “happy” chemicals that give you an instant head-to-toe feeling of pleasure.
