Scientifically, we would say that you have excited a standing wave in the string. The guitar string is not moving in the sense of shooting off to the other side of the room. In this sense, the guitar string is not moving at all, but remains clamped to the guitar. But the guitar string is moving in the sense that it is vibrating when you pluck it.
If you pick one spot on the plucked string and look at it closely, it is definitely moving from one location in space to another, back and forth repeatedly.
By pulling the string, you transferred chemical energy in your arm to elastic energy in the stretched string. When you let go, the elastic energy was converted to motional energy kinetic energy as the string snapped back and started vibrating. The total kinetic energy of the entire string averaged over time is zero, since the overall string is not going anywhere with respect to the guitar.
But the kinetic energy of any small part of the string at a given moment is not zero. In this way, a plucked guitar string experiences local motion but not overall motion. An electron in an atomic orbital state acts somewhat like a plucked guitar string. It is spread out in a three-dimensional cloud-like wavefunction that vibrates. Whereas a guitar string vibrates up and down, an atomic electron wavefunction simply vibrates strong and weak. The frequency at which the electron wavefunction vibrates is directly proportional to the total energy of the electron.
Electrons in higher-energy atomic states vibrate more quickly. Because an electron is a quantum object with wave-like properties, it must always be vibrating at some frequency. In order for an electron to stop vibrating and therefore have a frequency of zero, it must be destroyed.
In an atom, this happens when an electron is sucked into the nucleus and takes part in a nuclear reaction known as electron capture. With all of this in mind, an electron in a stable atomic state does not move in the sense of a solid little ball zipping around in circles like how the planets orbit the sun, since the electron is spread out in a wave.
Furthermore, an electron in a stable atomic state does not move in the sense of waving through space. The orbital electron does move in the sense of vibrating in time. But the truth is more complicated than this simple picture depicts. Answer: ionization. Explanation: Atoms and chemical species lose or gain electrons when they react in order to gain stability.
Thus, typically, metals with nearly empty outer shells lose electrons to non-metals, thereby forming positive ions. The number of electrons depends on their position on the Periodic table in simple terms. Answer Expert Verified.
Group 17 halogens elements are in group fluorine F , chlorine Cl , bromine Br and iodine I. Electron gain enthalpy is defined as the amount of energy released when an electron is added to an isolated gaseous atom. During the addition of an electron, energy can either be released or absorbed.
Some external energy is needed to add the electron in their atoms. Electrons are extremely small. Electrons are very important in the world of electronics. The very small particles can stream through wires and circuits, creating currents of electricity. The electrons move from negatively charged parts to positively charged ones. Electrons are involved in many applications such as electronics, welding, cathode ray tubes, electron microscopes, radiation therapy, lasers, gaseous ionization detectors and particle accelerators.
The exchange or sharing of the electrons between two or more atoms is the main cause of chemical bonding. An electron is a negatively charged subatomic particle. It can be either free not attached to any atom , or bound to the nucleus of an atom. Electrons in atoms exist in spherical shells of various radii, representing energy levels. The charge on a single electron is considered as the unit electrical charge. This corresponds to a single electron in an empty universe. Instead, they have probability distributions around the nucleus that take the form of the spherical harmonics.
Begin typing your search term above and press enter to search. Press ESC to cancel. Skip to content Home Social studies What role do electrons play in producing light? Social studies. Ben Davis January 29, What role do electrons play in producing light? Many LEDs have electrons that can only give up quanta of energy that, when converted into photons, produce light with a wavelength of about nm - which we then see as red light.
These electrons are so restricted in the quanta they can emit that they never shine blue light, or green light, or yellow light, only red light. Long, long before their were LEDs in our lives, scientists trying to understand electrons in atoms noted a similar phenomenon when light was either shone on certain materials or given off by certain materials.
They used Bunsen's burner to strongly heat tiny pieces of various materials and minerals until they were so hot that they glowed and gave off light. Sodium, for example, when heated to incandescence, produced a strong yellow light, but no blue, green or red. Potassium glowed with a dim sort of violet light, and mercury with a horrible green light but no red or yellow.
When Kirchoff passed the emitted light through a prism it separated out into its various wavelengths the same way a rainbow effect is produced when white light is used , and he got a shock.
He could only see a few thin lines of light in very specific places and often spread far apart. Clearly glowing sodium was not producing anywhere near all the different wavelengths of white light, in fact it was only producing a very characteristic band of light in the yellow region of the spectrum - just like a LED! Kirchoff and Bunsen carefully measured the number and position of all the spectral lines they saw given off by a whole range of materials.
These were called emission spectra , and when they had collected enough of them it was clear that each substance produced a very characteristic line spectrum that was unique. No two substances produced exactly the same series of lines, and if two different materials were combined they collectively gave off all the lines produced by both substances.
This, thought Kirchoff and Bunsen, would be a good way of identifying substances in mixtures or in materials that needed to be analyzed. So they did. In they found a spectrum of lines that they had never seen before, and which did not correspond to any known substance, so, quite rightly, they deduced that they had found a new element, which they called cesium from the Latin word meaning "sky blue".
Guess in what part of the spectrum they found the lines! All the research on atomic structure and the hideously difficult-to-understand properties of electrons come together in the topic of "electron energy".
An atom such as lithium has three electrons in various orbitals surrounding the atomic center. These electrons can be bombarded with energy and if they absorb enough of the quanta of energy being transferred they jump about and in the most extreme case, leave the lithium atom completely. This is called ionization. Partly this difference in the amount of energy needed to dislodge different electrons away from the lithium atomic center is due to the fact that the center of the lithium atom is carrying the positive charges of three protons.
Moving a negatively charged electron away from a positively charged atomic center needs more and more energy as the amount of un-neutralized charge increases, thus;. However, the amount of energy needed to remove the first electron is a good measure of what it takes to stimulate an electron to leave its atom, and how tightly it is held there in the first place.
Within the atom, as Bohr pointed out, there are different possible positions for electrons to be found as defined by the principal quantum number , usually written as " n ".
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