# 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.

###### 2,846 Questions
Science
Solid State Physics

# What materials do not conduct heat easily?

Some of the best are gases such as carbon dioxide, nitrogen, oxygen, etc. Perlite is extremely non-conductive. Ordinary materials like paper, wood and rubber are also relatively poor conductors. Please see the link.

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Math and Arithmetic
Physics
Solid State Physics

# How do you calculate lift over speed governor tripping speed?

Use a tacometer drive the governor round with an electric drill and measure the speed the govenor trips. lift govenor speeds are factory set

798081
Solid State Physics
Quantum Mechanics

# What is quantum mechanics?

Quantum mechanics is the mathematical description of matter on an atomic and subatomic scale. It is focused around the wavefunction of a system. Wave functions contain all information about the system such as: momentum, position, angular momentum, energy, etc. This information can only be known by its respective probability distributions. The basis of quantum mechanics in the wave mechanics formulation is the Schrodinger equation, which has two forms: the time-dependent and the time-independent.
Quantum mechanics is a branch of mechanics concerned with mathematical modelling of the interaction and motion of subatomic particles.

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Solid State Physics

# Heat conduction is most efficient in what type of substance?

Metallic

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Solid State Physics

# Do heavier objects roll faster than lighter ones?

Rolling is more complicated than falling. The angular momentum of an object depends not only upon the speed of rotation and the mass, but also upon the location of the center of gravity of that object; as the mass become farther from the axis of rotation, it will have more angular momentum for a given speed of rotation. So the shape of the object matters, and the distribution of mass in an object that is not uniform in composition. But let's say that you have two objects of exactly the same shape, and uniform density, both homogeneous spheres, for example, but one is heavier than the other. In that case the result is the same as for dropped objects; the increased mass causes an increase in inertia that exactly matches the increase in gravitational force, so that the acceleration is the same.

If we consider air friction as well in this case (where the objects are completely identical except their weight), then the heavier object will be faster.

The air friction is the same for both objects, but the heavier object will be less affected by this due to its larger inertia.

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Solid State Physics
Scientific Method

# Which has the most energy particles in steam particles in liquid water particles in ice or particles in freezing water?

The particles have most energy in particles in steam.

In a gas. the particles move more freely, Therefore, there is more energy in the steam.

:D

LOL

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Science
Chemistry
Solid State Physics

# Is soot an amorphous solid?

yes.

676869
Solid State Physics

# Which characteristic could distinguish a crystalline solid from an amorphous solid?

The way it breaks

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Astronomy
Math and Arithmetic
Physics
Solid State Physics
Speed of Light

# How far could you travel in one year at the speed of light?

6 trillion miles

414243
Inventions
Electronics Engineering
Solid State Physics

# How does a transistor work?

There are two kinds of transistor: Bipolar Junction Transistors (BJTs) and Field Effect Transistors (FETs). These two transistors work in two different ways. However, both types of transistors are based on the fact that when a voltage is applied to impure semiconductor such as Silicon, it changes from a conductor to an insulator or vice versa.

Field Effect Transistors contain a narrow conductive channel which passes near a "Gate" electrode. The two ends of this channel are connected to terminals called "Source" and "Drain." When a voltage of the correct polarity is applied between the Gate and the transistor channel, the channel becomes wider, and if this polarity is reversed, the conductive channel narrows, or it even vanishes entirely. By changing the size of this conductive channel, the FET behaves as a voltage-controlled valve or switch. Since the Gate does not require any continuing current, the FET operation can be improved by including a layer of insulating glass (Silicon oxide) between the gate electrode and the rest of the transistor. This type of FET is called a "MOSFET," for Metal-Oxide-Semiconductor layers. Transistors without the glass layer are called JFETs or "Junction-FETs."

Bipolar transistors are composed of three segments called "Collector," "Base," and "Emitter." A thin insulating layer arises naturally between Base and Emitter. If a voltage of the correct polarity is applied to the Base and Emitter terminals, the insulating layer becomes so thin that it behaves as a conductor. If this voltage polarity is reversed, the insulating layer becomes wide. By changing the thickness of this insulating layer, the BJT behaves as a voltage-controlled valve or switch. HOWEVER, whenever the Base-Emitter voltage is causing the insulator layer to become thinner, there also is a leakage current in the base terminal. This tiny current is proportional to any larger current passing through the entire transistor. Although the BJT is controlled by the voltage between Base and Emitter, designers usually ignore the base-emitter voltage, and the BJT is treated as a current-controlled valve or switch.

All transistors are made of a "doped" semiconductor, typically silicon. Pure silicon contains almost no movable charges, so it behaves as an insulator. To create transistors, the silicon crystal has impurities deliberately introduced during manufacture. Each impurity atom will "donate" a movable charged particle in the silicon, which changes the silicon into a conductor. Doped silicon is very different than metal conductors. The charges within metals behave like a dense liquid, while the charges in doped silicon behave as a highly compressible gas. Doped semiconductor is a special kind of conductor where an externally-applied voltage can easily "compress" or sweep the charges away. By sweeping the charges away, the semiconductor is changed from a conductor back into an insulator. Semiconductors are like electric switches or valves, but with no moving parts.

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Physics
Mechanics
Solid State Physics

# What does a photocell do?

photo cell convert light energy into electric power

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Chemistry
Solid State Physics

# Are humans a form of energy or solid matter?

If you want to delve into the depths of quantum physics, all matter is a form of energy. Therefore, humans being made of matter are energy. If you do not want to go that far and want to stick with classical physics, humans contain mass and are made of solids, liquids and gases. It all depends on your point of view.

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Physics
Solid State Physics

# How does a lever help make work easier?

a lever makes work easier in the sense that it help carry a heavy load from the ground in a process called lifting!

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Earth Sciences
Solid State Physics

# What would happen if the Earth's plates stopped moving?

there would be a lot less earthquakes and volcanic eruptions.

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Technology
Solid State Physics
Spectroscopy
Optics

# What is meant by Fresnel distance in optics ie diffraction how is it related to validity of ray optics please do make it simple as i am a beginner?

An aperature OS size a illluminated by a parallel beam sends diffracted light into a angle of approximately ~y/a. This is the angular size of the bright central maximum. In trevelling a distance z, the diffracted beam therefore acquires a width zy/a due to diffraction. this gives distance beyond which divergence of the beam of width a becomes significant. Therefore, z ~ a2/y we define a quantity ZF called the Fresenls distance by the following equation ZF= a2/y

For distance greater than ZF the spreading due to diffraction over that due to ray optics. The above equation shows that ray optics is valid in the limit of wavelength tending to zero.

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Electronics Engineering
Physics
Solid State Physics

# Zinc Sulfide is whether the direct band gap semiconductor or indirect band gap semiconductor?

It is direct band gap material.

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General and Special Relativity
Solid State Physics

# How is a steel ball more elastic than a rubber ball?

Elasticity is measured as Young's Modulus (a.k.a Modulus of Elasticity).

Young's Modulus is equal to the maximum stress that can be placed on an object that will not PERMANENTLY alter the shape of the object over the strain (think deformation) induced by that stress.

************** Elasticity is a Measure of Stress/Strain **********************

Larger stress with little strain = more "elastic"

So,

A steel ball can undergo a large amount of stress with very little stain induced.

A rubber ball on the other hand will show a larger amount of strain (deformation) with a smaller amount of stress placed on it.

Example:

The stress-strain curve below shows steel compared to a polymer and a rubber. As you can see, steel can have a lot of stress placed on it with little deformation while rubber has large deformation with little stress.

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Solid State Physics

# How fast are the wind inside a tornado spinning?

Winds range can range from 65mph to over 300mph.

Most tornadoes are rated EF0 with estimated winds of 65mph to 85 mph.

The greatest damage comes from EF3 and stronger tornadoes with winds over 135 mph.

Few than 1 tornado in every thousand is rated EF5, with winds over 200 mph.

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Chemistry
Solid State Physics
Elements and Compounds

# What is radium used for?

Self-luminous paints (only in the past, before 1930), Ra-Be neutron sources, preparation of radon from RaCl2 solutions, medical uses for the treatment of conditions such as cancer (now being replaced by radioactive cobalt, 60Co sources, 137Cs, etc.).

Its use in medicine has declined because of its cost, and its use in consumer goods (to illuminate watch and clock hands and numbers, as well as instrument dials) was halted because it can cause radiation injury. It is still used for some radiography and as a source of neutrons.

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Solid State Physics

# What is the solid state diode?

A solid-state diode is a diode where the electrons flow through only solid materials. Nearly all diodes in common use are solid-state.

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Solid State Physics
Physics

# How do you memorize physics long answers?

I don't, I make a mental model. When I need it, I run the mental model and automatically "see" the full answer.

I know this is hard for most people to understand, I don't know myself how I am able to do it and most others can't. If you have never "watched" one of these models run, you probably couldn't believe anything could look like that (software models are especially surreal and abstractly colored).

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Mechanical Engineering
Solid State Physics

# Explain the working and constructions of bragg's spectrometer?

Constructin:

It works like an optical spectometer.X-rays frm an Xray tube are incedent on a crystal at some glancing angle 'b'.Since they r to be incedented in form of narrow beams slits of lead plates are used.the crystal is mounted on a turntabe which can move along a vertical axis.circular scales are mounted on the turntable to measure the ange'b'.At some point it consists of an arm which has a detector attached to it.when the turntablle moves with an ange'b' the arm moves with angle 2b.this way the X-ray beam is always incidented inside the detector.The ionising current produced by the reflected beam is merasured by a sensitive electometer E or recorded on photographic plates.

Working:

Initially the angle b is adjusted to 0 deg.With this the detector is so adjusted to receive the beam inside it.Then the crystal is moved in small angles and the correspnding deflections is noted down.A graph is ploted of Ionization current vs glancing ange.

This is used to verify Bragg's law.

ie sin a:sin b:sin c=1:2:3.

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Solid State Physics

# Why white sand doesn't heat?

Because it has high reflectivity. That's why it's white it reflects not particular colors but white (all colors together).

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Units of Measure
Physics
Chemistry
Volume
Solid State Physics

# The amount of matter in one unit of volume?

That is called the density - mass / volume. The SI units are kilogram / cubic meter.

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Physics
Mechanical Engineering
Solid State Physics