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Solid State Physics

Solid State Physics is the branch of physics that deals with the physical properties of solid materials, especially the electromagnetic, thermodynamic, and structural properties of crystalline solids.

813 Questions

Does sugar still have volume when it is dissolved in water?

Yes, it certainly does, although not necessarily the same volume it did when it was a solid. When you add sugar to water and dissolve it, the volume of the sugar water will be greater than the volume of the water before you added it.

You can determine how much the volume changes by just measuring the volume before and after adding sugar and taking the difference. However, note that upon adding sugar to water and dissolving it, you can't treat it like "dissolved sugar" and "water" separately. They are now a solution and you can't really separate the volume of sugar molecules unless you talk about molecular size and Van der Waals radii and other complicated effects when water interacts with solutes on a molecular level. So while the volume will certainly change when you add sugar and dissolve it in water, exactly what amount of that change is due to the molecular size of sugar molecules and what is due to other effects is difficult to determine exactly.

* Sucrose's concentration is 4.636 M: (1587 g/L)/(342.2965 g/mol). * Water's concentration is 55.51 M: (1000 g/L)/(18.0153 g/mol) * 2.5 M of solution is 1316.3 g/L. Its molar fraction is .04156 M/M: 2.5/4.636+55.51. * The density-guess would be 1024.4 g/L: .04156(1587 g/L)+.95844(1000 g/L). The solute's proper volume is thus 2039.2 g/L: (1587 g/L)(1316.3 g/L)/(1024.4 g/L). Of course it does; all materials take up volume, other than fictional objects such as black holes. They like each other, so they shrink.

If Pu239 emits alpha particles of energy 5.4Mev calculate the decay probability?

It is possible to relate a decay constant of some α emitting nucleus to an energy of α particle in the framework of the Gamow theory (see Related links) that is based on the quantum mechanics description of the tunneling through the potential barriers.

Previous view (by Quirkyquantummechanic)The fact that 239Pu decays by alpha particle emission (with the α particle coming away at 5.245 Mev) has nothing to do with this isotope of plutonium's decay probability. The decay probability of 239Pu (or anything else) can be expressed as a distribution function. That's math speak. What that means is that any nuclear decay event has "odds" that it may happen. Let's look at that a bit.

All unstable radionuclides will eventually decay. But when? Well, they all have some, um, "quirks" about them. Some take a long time to eventually fall apart, but some don't take that long. All we can do is "average out" the decay of a given material. Got that idea? It's important. And one of the ways we talk about the decay probability is in terms of something called the half life of a material. In the case of 239Pu, for example, the half life is 2.41 x 104 years. That's 24,100 years. What that means is that if we have a kilogram of the stuff, in 24,100 years, only half of the plutonium we started with will be left. Make sense? Mmhmm. But check this out. If we have two atoms of the stuff, does that mean that in 24,100 years only one will be here? No, it does not. They could both decay in the next week or the next month. Or the next century. Half life is a "probability thing" with unstable materials. And it is calculated across a "curve" of probability (that distribution function we mentioned) based on measurements of a quantity of the material being considered. It's that simple.

As an aside, but on a related note, if you guessed that the artificial elements (we call them synthetic, because they must be synthesized or made) that we know of by only a few atoms don't have very accurate measurements of their half lives, you'd be absolutely right. It's really difficult to (with accuracy) "guestimate" the half life of something, of some element, that is known from only a dozen atoms of the material....

Why silicon is preferred over germanium in the fabrication of p-n junction diode?

Germanium diodes are more expensive than silicon ones, germanium is harder to process, germanium cannot be used to make integrated circuits (while early prototype integrated circuits were germanium the wiring between the integrated components cannot be integrated making it too expensive for production), germanium cannot operate with a junction temperature above 60C (silicon will operate up to 150C), and its reverse leakage current is greater. However! Germanium diodes have a lower forward voltage drop than silicon ones do, so they're better for some applications, like radio frequency detection.

What is a unit cell?

A unit cell is the smallest repeating structure that fully represents the symmetry and arrangement of atoms in a crystal lattice. It is used to describe the spatial arrangement of atoms or molecules in a crystal lattice and is replicated throughout the crystal to form its structure.

What is the smallest thing visible?

Russell

Under certain conditions you can see a reaction occur between 2 atoms at a distance of 2 metres. and most people can be taught the necessary focus techniques required, unfortunately those who have poor eye sight and who require glasses cannot.

Find a window which looks to a blue sky, stare into the world beyond the floaters, some you cannot follow, follow the one's you can, observe and you will see.

This is the doorstep to the world of neutrino's and their like.

What is the relationship between the velocity of propagation in a t.t.l and the speed of light?

I don't know what a t.t.l is but I do know that the propagation of the speed of light compared to velocity is explained in Einstien's Special Theory of Relativity. It basically states that as an object approaches the speed of light, distance becomes greater, and time slows down (compared to an object at rest). Unfortunately, there is no way to truly tell if you are at rest. Sure you can say that you are at rest if you are standing still but realize that the Earth is moving through the galaxy at some 30,000 mph at this very moment. The reason for the change in time and space is that the speed of light is constant, no matter how emitted or recorded. This means that light will travel at the speed C even if you are moving at C/2 to begin with. someone approaching you at the same speed will witness the light pass them at the speed C. Someone else standin still (compared to the other two) will also witness the light pass by at the speed C. Get the point? If you need more information just read Einstiens relativity book on the special and general theory; it's tough reading, but it explains everything.

Would an object shrink when traveling at the speed of light?

The object would probably disintegrate completely. The speed of light is 299,792,458 meters per second, that's fast enough to circle the globe at least 6 times. The force against the wind would have to be at least 500,000 pounds of pressure, and that's an underestimation. The object would most likely catch fire, as well.

What state of matter is the mind?

The mind is not any state of matter.

The mind is an epiphenomenon of the electrobiochemistry happening in the unbelievably complicated network of neurons, myelin, neurotransmitters, neuromodulators, neuroregulators, hormones, etc. that make up the about three pounds of largely fatty tissue enclosed in our bony skull that we refer to as a brain.

What happens to the printed words when viewed through the drop of water in the plastic cover?

When printed words are viewed through a drop of water on a plastic cover, refraction occurs. Refraction causes the light passing through the water drop to bend and distort the image of the printed words. This effect makes the words appear enlarged and upside-down when viewed through the water drop.

Why is it possible to boil water in a thin paper container but not in a cardboard container?

Thin paper containers can withstand the heat of boiling water because they have minimal insulation and can transfer heat effectively. Cardboard containers, on the other hand, have thicker layers and more insulation, which makes it difficult for the heat to transfer efficiently, resulting in the cardboard being unable to withstand the heat and potentially catching fire.

What is inside one of the open spaces of an ice crystal?

There is nothing inside one of the open spaces of an ice crystal. Air would show O2 or N2 within the space, which are comparable in size to water molecules. Any water vapor in the spaces would have to show free-roaming water molecules. Therefore the space is filled with nothing.

What is meant by 1 general multiplicity 2 chemical occupancy 3 site multiplicity 4 occupation number in crystallography?

  1. In crystallography, "general multiplicity" refers to the number of symmetry operations (such as rotations or reflections) that can be applied to a crystal lattice to generate equivalent positions.
  2. "Chemical occupancy" refers to the number of atoms occupying a specific position in the crystal lattice. It indicates the stoichiometry (ratio of different atoms) within the crystal structure.
  3. "Site multiplicity" refers to the number of equivalent sites (positions) within a crystal lattice that are indistinguishable based on the crystal's symmetry elements.
  4. "Occupation number" refers to the number of atoms or molecules occupying a specific site in the crystal lattice. It indicates if the site is fully occupied (1.0), partially occupied (less than 1.0), or vacant (0.0).

Name and describe the state changes in which solids and liquids become gases.?

The state change in which a solid becomes a gas is called sublimation. This occurs when a solid substance directly transitions into a gas without passing through the liquid phase. The state change in which a liquid becomes a gas is called evaporation or vaporization. This occurs when a liquid substance turns into a gas by absorbing heat energy.

Why liquids are less common than other two states of matter on earth?

Liquids are the least common of the four states of matter due to the temperatures/conditions in which they exist. Gases exist in a very high range of temperatures, as do solids, but liquids require specific temperature ranges (generally very small ones) in order to exist.

Is flower a liquid or a solid?

A flower is neither a liquid nor a solid. It is a plant organ that consists of various parts, including petals, sepals, stamens, and pistils. It is considered a solid object.

Example to demonstrate friction?

Yes, cars have less friction when they roll on the ground than when the breaks are on (sliding). That's why breaks stop the car, because the sliding friction of rubber on asphalt is very high.

Is gak a solid or liquid and why?

Gak is a liquid and solid. In the school science lab ,I did an experiment and made gak out of borax, water, saturated water, Elmer's White glue, and food coloring.If you mush it feels like liquid and if you leave it somewhere it will look like it is frozen and it will look like it is a solid.

What is the breakdown voltage of PN junction diode?

A Zener diode doesn't allow almost any current to flow below a certain voltage. Above this voltage (the breakdown voltage), the amount of current that can flow is almost unlimited; meaning that the device acts as an "open" for lower voltages, and as a "short" for higher voltages.

Why transistor cannot be used as rectifier?

By connecting collector to base, you get a *lower* forward voltage drop than with a simple diode.

Example: germanium diode-connected transistor has a drop of about 0.13 volts, rectifier diode about 0.3 (over 2.5 times)

It's just that rectifiers are optimised for rectification, are designed to work at (generally) higher currents, and are cheaper.

What is matter with slow moving particles?

Please clarify what you mean by slow-moving air. Do you mean an air mass that is moving slowly, or a gas particle that is moving slowly?

If you mean the latter, perhaps this answers your question: for a given temperature, gas particles with less mass move faster than gas particles with greater mass. Additionally, for a given species, a lower temperature corresponds to lower particle velocity, with absolute zero corresponding to no movement whatsoever.

How do earthquakes change the land?

Depending on the environment they are in when they occur, earthquakes can:

- create faults and folds in the earth's crust

- trigger local volcanoes

- create tsunamis

- destroy local man-made buildings and/or structures

Can you liquefy oxygen at -183 Celsius?

At atmospheric pressure, yes. This is the melting point of oxygen at one ATM. The process is usually done as follows:

1) Air is filtered and put into a chamber.

2) It is then compressed. Pressure rises, so temperature increases. The pressurized gas chamber gives off some of its heat.

3) Then the reverse happens- the gas is expanded quickly. The resulting release in pressure makes the temperature go down.

4) One cycle is not enough. The cold air at the end of the cycle is used to cool down air coming in in step one. This means that the incoming air is colder to begin with, so the whole process gets closer.

Why are npn transistors used more often than pnp transistors?

The primary reason that NPN transistors are used more often than PNP transistors is that they usually operate faster (at higher frequencies) because the mobility of the current carriers in NPN transistors (electrons) is much higher than that of the current carriers in PNP transistors (holes).