Energy packets

Photoelectric effect The effect produced when electromagnetic radiation knocks electrons out of a metal. Einstein used this phenomenon to show that light was quantized and came in energy packets called photons. 

Quantum theory considers radiation as a stream of energy packets - photons or quanta - travelling through space at a constant velocity (c when in a vacuum). The energy of a photon is related to the frequency of the radiation, as defined in wave theory, by the expression... 

The quantal energy packets are so small that the total stored molecular energy (the sum of all the molecular excitation quanta) is perceived at the macroscopic level as the continuously variable temperature T rather than a countable microscopic quantity. However, this countable aspect of molecular-level energy excitations underlies proper evaluation of Boltzmann s ft (number of possible molecular microstates consistent with total macrostate energy), and thus the entropy. 

Light is quantized, which means it consists of a stream of energy packets. Each packet is called a quantum, also known as a photon. 

Breadth in the Packaging" uf Energy. In Fig. I a packet of energy of 1 joule (I newton-meter) is represented by Ihe box in the upper center. Various energy packets, ranging from I electron volt (10 1-1 joule) to the daily energy output of the sun (total — in all directions) of IU joules are indicated. 

Stanley Miller was impressed by the ease of synthesis of adenine from simple molecules, but the cell eschews simple synthesis. In fact, if we dissolved in water (using the formal chemical names) ribose-5-phosphate, glutamine, aspartic acid, glycine, N10-formyl-THF, carbon dioxide, and energy packets of ATP and GTP—all the small molecules that are used by the cell to build AMP—and let them sit for a long time (say, a thousand or a million years) we would not get any AMP.8 If Stanley Miller mixed these chemicals hoping for another rock of the faith, he would be quite disappointed. 

First, we can ask a relative question Is interfacial electrochemistry simply a special aspect of reaction kinetics, somewhat analogous to photochemistry In photochemistry, one might say, one studies the effect of energy packets (photons) striking molecules in electrochemistry, one studies the effect of striking molecules dissolved in solution with electrons emitted from electrically charged conductors. 

In addition to possessing wavelength characteristics, light also has properties that indicate it is composed of discrete energy packets called photons. The relationship between the energy of photons and their frequency is given by the equation ... 

Photons Energy packets of electromagnetic radiation also known as quanta. 

Now suppose we are able to create a circuit in which the amount the current ramps up by in the on-time (AIon) is exactly equal to the amount the current ramps down by during the off-time (AIoff)- If that happens, we would have reached a steady state. Now we could repeat the same sequence an innumerable amount of times, and get the same result each and every time. In other words, every switching cycle would then be an exact replica of the previous cycle. Further, we could also perhaps get our circuit to deliver a steady stream of (identical) energy packets continuously to an output capacitor and load. If we could do that, by definition, we would have created a power converter ... 

To explain the photoelectric effect, Einstein assumed that the radiant energy striking the metal surface behaves like a stream of tiny energy packets. Each packet, which is like a particle of energy, is called a photon. Extending Planck s quantum theory. 

Electromagnetic radiation comes in small energy packets, known as photons. These have an energy equal to hv, where h is Planck s constant and v is the frequency. Photons also have a momentum, p, which is given by the equation, p = A/A, where A is the wavelength. 

In the quantum theory, energy is quantized, meaning that it can have only certain allowed values. Einstein used the quantum theory to explain the photoelectric effect, the emission of electrons from metal surfaces when exposed to light. He proposed that light behaves as if it consists of quantized energy packets called photons. Each photon carries energy, = hv. 

Planck tried to interpret the physical significance of his lucky guess.He believed that energy packets were a temporary adaptation and that the size of his packets could become vanishingly small until he would be left with comfortable, continuous physics. But this... 

Bohr postulated that there can be only certain discrete orbits for the electron around a nucleus—called stationary states—and that to go from one state to another, an atom must absorb or emit a packet of just the right amount of energy—a quantum. He then proceeded to predict the position of the lines in the hydrogen spectrum based on Balmer s formula, Planck s energy packets, the mass and charge on an electron, and his quantized orbits. 

Light can also be considered to be composed of energy packets called photons, which behave like particles. 

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