OpenLLM-France/wikimedia huggingface dataset:
# A-level Geography/AS OCR Geography/Cold environments
## Types of cold environment
### Glacial

* Snow and ice all year round
* Dry climate
* Temperatures stay below 0 °C

### Periglacial

* Significant snow and ice cover but not all year round
* Temperatures rise above freezing during summer
* Low precipitation

### Upland

* Once covered in snow
* Can be periglacial
* Wet climate due to orographic rainfall

## Processes
### Plucking

The ripping of material from the bedrock of a glacier
It occurs when there is a large downwards pressure from the weight of glacier. As the glacier moves downwards, friction between the basal ice of the glacier and the rock below causes melting. This water freezes to obstacles, which are then 'plucked' from the bedrock.

### Abrasion

The sandpaper effect
It occurs when there is material present at the base or sides of the glacier. This material is dragged along the rock, erasing it. This process may cause grooves called striations to be formed. The larger and more angular material causes the most erosion.

### Freeze-thaw

The weathering of rock with water
It occurs when water, which has penetrated cracks or fractures in rock, freezes. Water expands approximately 9% when it freezes so this expansion puts pressure on the rock. Repeated freezing and thawing (over many years) can lead to fracturing. As this process relies on fluctuating temperatures, it is mainly seen in periglacial areas.

### Chemical weathering

The weathering of carbonate rocks by carbonic acid
It occurs when CO$_2$ in the air dissolves into rainwater, forming a weak carbonic acid. CO$_2$ is more soluble at lower temperature, so therefore the water becomes more acidic. This acid then reacts with carbonate rocks, such as limestone, dissolving them.

## Glaciers
### Ice Formation

* Snow is compressed by the weight of subsequent snowfalls. Compacted snow which has experienced a winters freezing and a summers melting is known as firn. For this to happen, the summer must have low temperatures.
* As more snow builds onto of the firn, air is squeezed out, and ice is formed.
* Ice accumulates as more snow falls.
When this ice flows downhill under its own weight and gravity, it's called a glacier.

### Types

* Ice sheets - largest glaciers (Antarctica)
* Icefields/icecaps - miniature ice sheets (Uplands)
* Valley glaciers - flow down mountainous regions (Alps)

### Zones

* Upper Glacier - Accumulation (input>output)
* Lower Glacier - Ablation (input<output)
* Zone of Equilibrium - Snow line (input=output)
The glacial budget is the difference between total accumulation and total ablation/year.
# A-level Graphic Products/Edexcel

This is a book about A-Level Graphic Products. It aims to fit in with the Edexcel GCE A-Level Product Design syllabus but is not endorsed by Edexcel. It should be useful as a revision guide or to find alternative explanations to the ones in your textbook. If you haven't heard of an A-Level then this book probably won't be of much interest to you but you can find out about them at Wikipedia.
Please note that the last opportunity for the sitting of the GCE EDEXCEL GRAPHIC PRODUCTS qualfication (9GR01,9RM01,8GR01 & 8RM01) is JUNE 2017 for AS candidates and JUNE 2018 for A2 candidates. After this, EDEXCEL is replacing the qualification with the new 2017 - 9DT0 course. This textbook has been designed specifically for the older qualification.
If any part of this book is unclear or even wrong then please post a comment on the discussion page or simply fix it yourself! In particular, please say if the book assumes any knowledge or skills which not all A-Level Product Design students have.

## AS modules

50% of GCE OR individual AS qualification
* Unit 1 :Portfolio of Creative Skills
60% of AS qualification, 30% of total GCE
* Unit 2 :Design and Technology in Practice
40% of AS qualification, 20% of total GCE

## A2 modules

50% of GCE
* Unit 3 :Designing for the Future
60% of A2 marks, 30% of total GCE
* Unit 4 :Commercial Design
40% of A2 marks, 20% of total GCE

## External links

Question past papers: http://www.edexcel.com/quals/gce/gce08/dt/product/Pages/default.aspx (Just make sure you don't select resistant materials)
# AQA A-Level Physics/Particles and Anti-particles/Forces

You may have learnt that there are many different types of forces such as friction and tension. However only four fundamental forces are at a basic level responsible for all interactions in the universe.

## Strong Nuclear Force

This type of force is only experienced by hadrons (baryons and mesons). The exchange particles for this force are gluons. This force is responsible for keeping the protons and neutrons in a atomic nucleus together. The strong nuclear force only acts over a short range of 3fm. Between the distance of 3fm and 0.5fm separation the strong nuclear force is attractive. Below 0.5fm separation the strong nuclear force is repulsive.

## Weak Nuclear Force

This type of force is experienced by both hadrons and leptons. The exchange particle for this type of force is the W or the K boson. This force is responsible for decay interactions (such as beta decay) and interactions where strangeness is not conserved or where quarks change flavour (or type).

## Electromagnetic Force

This type of force is experienced by particles which are charged (such as electrons and protons). The exchange particle for this type of force is the virtual photon. This force is responsible for the repulsion of two electrons and attraction of an electron to a proton.

## Gravitational Force

This type of force is experienced by all particles in the universe which have mass. The exchange particle for this force is not known and you will never be asked to mention it, but if you're curious, it is theorised that this force functions slightly differently to the other three. This force binds together all mass in the universe. No matter how far you stray from something, you will always be attracted to it, although the strength of this weakens with separation.
# AQA A-Level Physics/Particles and Anti-particles/Conserving and illustrating interactions
## Fundamental rules of particle conservation

4 Things must always be conserved in a particle interaction;
Charge, Baryon Number, Lepton number & Mass/Energy.
The first three are the ones which will most commonly come up in exam questions or be expected when asked to determine if an interaction could occur.
There is also 1 thing which is almost always conserved, being Strangeness.

### Conservation of Charge, Baryon Number & Lepton Number

Conservation of these factors is calculated using the values of these given in the formula book. For an interaction to occur, charge must be completely equal on both sides of the 'equation'.
It is important to note that the data given in the formula booklet regards quarks, so you must have knowledge of how quarks come together to form hadrons to answer these questions.

### Conservation of Mass/Energy

These conservations are mainly studied in the mechanics section, however, it is important to know that these will also come up in the 'Radiation' subtopic in particles. In the context of Particles and Radiation, the mass of a particle is equal to its energy at rest. This, and its applications will come up in the Radiation subtopic.

### Conservation of strangeness

Strangeness must be conserved in all interactions, except for weak interactions.
A weak interaction can be easily noticed in a few ways;
Weak interactions can change the flavour of quarks and leptons, while other interactions cannot.
In weak interactions, strangeness can vary by 1 either positively or negatively. So, for example, if there is a strangeness of 1 on one side, in a weak interaction, this can become either 0, or 1. It can also stay the same.

## Illustrating interactions
### Feynman Diagrams

to be finished

### In the Exam

To be finished
# AQA A-Level Physics/Nuclear Instability

Nuclear stability is linked to its number of nucleons (neutrons and protons). The nucleons interact with each other through the strong nuclear force, this must overcome the electrostatic repulsion between the protons to make the nucleus stable. When the electrostatic repulsion exceeds the strong force the nucleus is now unstable and will then change its nucleons causing radioactive decay. When the graph of number of neutrons (N) against protons (Z) is drawn, and all the stable istopes are plotted on it, there is quite a clear correlation between N and Z.
Initially stable isotopes are found on the line N=Z but soon the number of neutrons needed to keep the nucleus stable becomes larger than the number of protons and the stable isotopes curve away from N=Z. This is because as the nuclear radius increases a greater strong force is required to keep it stable but adding more protons will only increase electrostatic repulsion and so the number of neutrons becomes more than that of protons.
Radioactive decay occurs because a nuclei is unstable. It emits alpha particles, beta particles or gamma rays to become more stable.
$^A$$_Z$X
Z is the proton number (sometimes called atomic number) it is the number or protons in the nucleus.
A is the nucleon number (some times called mass number) it is the total number of protons AND neutrons in the nucleus.
N is the number of neutrons = A – Z
For light isotopes (up to Z=20) the stable nuclei have equal numbers of protons and neutrons for heavier nuclei to be stable they need to have more neutrons than protons.
* Nuclei with too many protons become more stable by emitting a beta+ (b+) particle when a proton converts into a neutron
* Nuclei with too few protons are to the left of the stability line and become more stable by emitting a beta- (b-)particle when a neutron converts into a proton
# AQA A-Level Physics/Nuclear Radius

When Ernest Rutherford first proposed the nuclear model of the atom in 1911,it enabled us to deduce the possible size for the atom. In Rutherford's experiment he fired a narrow beam of alpha particles (all with equal quantities of kinetic energy) in a vacuum to probe the structure of the atom. A thin strip of metal foil was placed in the path of the beam. Whilst most of the particles passed straight through the foil with very little or no deflection, approximately 1 in 10000 alpha particles were deflected by more than 90 degrees. The foil itself had to be very thin otherwise the particles could have been deflected more than once.
For this single scattering by a foil strip that has 'n' layers of atoms, the probability that an alpha particle is deflected by a given atom is therefore around 1 in 10000n. This probability does however depend on the effective area of cross-section of the nucleus to that of the atom. As a result, we can deduce the following...
For a nucleus of diameter, 'd', in an atom of diameter, 'D', the area ratio is equal to;
${\frac {{\frac {1}{4}}\pi d^{2}}{{\frac {1}{4}}\pi D^{2}}}$
Therefore...
$d^{2}={\frac {D^{2}}{10000n}}$
A standard value of $n=10^{4}$ gives $d={\frac {D}{10000}}$
Electron scattering
This is a good way to estimate the size of a nucleus but a more accurate way of measuring the nucleus is electron scattering. In electron scattering, electrons are fired in a beam at a sheet of the target material. The de Broglie wavelength of an electron is about 10$^{−15}$m. This means they are diffracted by the target material with the following relationship: 0.61λ/R=sinθ_min
# AQA A-Level Physics/Mass and energy

The mass-energy equivalence principle theorised by Albert Einstein describes the relationship between mass and energy through the equation $E=mc^{2}$. As $c^{2}$ is constant, $E\ \alpha \ m$. For example, 1kg of matter is equivalent to around $3\times 10^{8}$J of energy. This principle can be used to calculate the rest mass of a pair of particles which are produced through pair production, or the energy of a gamma photon produced through annihilation.
# AQA A-Level Physics/Momentum

Momentum Concepts- Force as a rate of change of momentum. This links to Newton’s Second Law, which states that the rate of change of momentum of an object is directly proportional to the resultant force applied and is in the direction of the resultant force. The resultant force is equal to the rate of change of momentum.
Impulse: Impulse of a force is finding the product of the force acting on an object and the amount of time it’s having the force act upon it. Impulse is a vector quantity and its units are in kilogram metre per second, or Newton seconds. From this we can find that the impulse is the equal to the change in momentum of an object.
Area under a force-time graph: This area shows us the impulse of the force applied, which in turn tells us the change in momentum of the object. Principle of the conservation of momentum: The principle of the conservation of momentum when two objects interact the total momentum remains the same providing there are no external forces acting on the system.
Elastic and Inelastic Collisions: Elastic collisions are those in which the kinetic energy is conserved. You have the same total kinetic energy at the end as you do at the start. Inelastic collisions are when some energy is lost from the system and so the kinetic energy does not remain the same. Some of the kinetic energy will have been dissipated to the surroundings the form of other energies, such as heat or sound.
# AQA A-Level Physics/Particles and Anti-particles/Constituents of the particle

You may have learnt that matter is made up out of three types of particles; protons and neutrons in the nucleus and electrons orbiting around outside. You might think that these particles are the basic building blocks for all matter. While it is true that the electrons cannot be broken down into any smaller particles, it is possible to smash up protons and neutrons into smaller bits. For this reason we say that the electron is a fundamental particle and that protons and neutrons are not fundamental.
The electron belongs to the family of fundamental particles called Leptons. These small particles typically have very small masses. The proton and the neutron belong to a family of heavier particles called Baryons.

## What makes up the proton and the neutron?

Protons and neutrons are made up of smaller, fundamental particles known as quarks. Just like all of the other baryons, protons and neutrons consist of three quarks. The three quarks add together to make the baryon, so in the case of a neutron we require the charges on the quarks to cancel out. In the case of the proton the charges must add up to give e.
To keep things simple in Particle Physics, we can call the proton charge +1 and give each quark a fractional charge as shown in the table below.
| Name | Charge | Baryon Number | Strangeness |
| Up (u) | +2/3 | 1/3 | 0 |
| Down (d) | -1/3 | 1/3 | 0 |
| Charm (c) | +2/3 | 1/3 | 0 |
| Strange (s) | -1/3 | 1/3 | -1 |
| Top (t) | +2/3 | 1/3 | 0 |
| Bottom (b) | -1/3 | 1/3 | 0 |

## Explaining the properties of quarks

The first thing you'll be unfamiliar with is the term Baryon Number.This is a term that's basically either as "yes" or "no", and it's called boolean, so yes is +1 and no is 0. If there's an anti-particle, the number will be -1.
Anti-particles exist, and so do anti-quarks! They're represented with what's known as a bar, which is drawn above the shorthand name, so for instance, we have ${\bar {u}}$ for a u-bar, an anti-up-quark! So, let's look at how a proton is made of quarks! Look:

## An example of calculating quarks

A proton, is made up of 3 quarks, and so is a neutron, because it's a pretty big particle in comparison to others. So, we remember from before that a proton is a baryon, and it must therefore have a baryon number of +1 and a charge of +1. So, let's start off.
$U$ = Charge of +2/3 and a baryon number of 1/3. So, we add that to: $D$ = Charge of -1/3 and a baryon number of 1/3, so we have... $+2/3+-1/3=+1/3$ charge and a baryon number of 2/3. $U$ = Charge of +2/3, so we add that to the +1/3 of U + D, and we get +1 (the charge of a proton) and a baryon number of +1!
# AQA A-Level Physics/Particles and Anti-particles/Creation and annihilation 2

Creation and Annihilation
This is part of topic 1.4 in the AQA Physics A syllabus. The main of the topic covers about Particles and antiparticles. And how there is an antiparticle for every particle in the universe. The theory of antimatter was first predicted by Paul Dirac in 1928 and has since been proved. However creation and annihilation in basic forms is either, when a photon creates a particle and an antiparticle or when a particle and an antiparticle collide creating a photon.
Creation
There are in fact many different types of creation; however in this syllabus there is one mentioned specifically, Pair Production. In Pair Production a photon creates a particle and a corresponding antiparticle, and vanishes in the process. For a particle and antiparticle, each of rest energy E$_0$, we can calculate the minimum energy and maximum frequency f$_{min}$ that the photon must have to produce this particle – antiparticle pair. Remember, c is the speed of light in a vacuum (3.0 x 10^8ms^-1).
Minimum energy of photon needed = hf$_{min}$ = 2 E$_0$
For example, the electron has a rest energy of 0.511 MeV. Therefore, for pair production of an electron and a positron from a photon:
The minimum energy = 2 x 0.511 MeV = 1.022 MeV = 1.64 x10^-13 J
A photon with less energy could not therefore create a positron and an electron.
Annihilation
Annihilation occurs when a particle and a corresponding antiparticle meet and their mass is converted into radiation energy. Two photons are produced in the process (as a single photon only would take away momentum which isn’t allowed, as no outside forces act). Therefore, the minimum energy of each photon, hfmin is given by equating the energy of the two photons, 2hf$_{min}$, to the rest energy of the positron and of the electron (i.e. 2hf$_{min}$ = 2E$_0$, where E$_0$ is the rest energy of the electron.)
Minimum energy of each photon produced, hf$_{min}$ = E$_0$
# America's Army: Special Forces

America's Army: Special Forces is a guide by and for players of the computer game America's Army. For this reason its tone and point of view are not detached and the guide does not make a clear distinction between fact and fiction, lacks references and sources and may be confusing for readers unfamiliar with the game.
This page applies only to version 2.7 (Release Date: 14th September 2006) of America's Army: Special Forces.

## Training

* Basic Marksmanship Training
* Obstacle Course Training - Eagle Tower
* Weapons Familiarization
* MOUT Single Player Training - MOUT Shoothouse
* Advanced Marksmanship Training - M24 training, M82 training
* Airborne Training - 250 foot Jump Tower, Live Jump
* Medic Training - Breathing control, Bleeding control, Treating shock, Field training
* Special Forces Training - SF Assessment and Selection AVWID, Escape and Evasion
* Advanced Training - Driver Training, CROWS gunnery training, and Javelin Training

## Tactics
### General

* Basic Tactics/Hints
* Stealth Tactics
* Timing tips for Close Quarters situations

### Multiplayer Maps

* Border Tactics
* Bridge Crossing Tactics
* Bridge Crossing SE Tactics
* Collapsed Tunnel Tactics
* Dusk Tactics
* FARP Raid Tactics - Farm Raid
* FLS Assault Tactics
* HQ Raid Tactics
* Insurgent Camp Tactics
* Interdiction Tactics (coop)
* Mountain Ambush Tactics
* Mountain Pass Tactics
* Mountain Pass SE Tactics
* MOUT Mckenna Tactics
* Pipeline Tactics
* Radio Tower Tactics
* River Basin Tactics
* Steamroller Tactics
* Swamp Raid Tactics
* Weapons Cache Tactics
* Weapons Cache SE Tactics
* Woodland Outpost Tactics
* Urban Assault Tactics

### Special Forces Multiplayer Maps

* Pipeline SF Tactics
* SF Arctic Tactics
* SF CSAR Tactics
* SF Courtyard
* SF Dockside Tactics
* SF Extraction Tactics
* SF Hospital Tactics
* SF Recon Tactics
* SF Oasis Tactics
* SF Sandstorm Tactics
* SF Taiga Tactics
* SF Water Treatment Tactics
* SF Snake Plain Tactics

## Weapons and Equipment
### US Equipment

* M16A2 Rifle
* M4A1 Rifle
* M203 Grenade Launcher
* M4 SOPMOD
* M249 SAW
* M24 Sniper Rifle
* M82 Sniper Rifle
* SPR Special Purpose Rifle
* M9 Pistol
* AT4 Anti-tank Launcher
* Javelin Anti-tank Launcher
* Night Vision Goggles
* MILES
* Parachute
* M2 .50Cal
* Mk.19 40mm Grenade Launcher

### US Vehicles

* HMMWV M1114 Uparmored

### OpFor/IF Weapons

* AK47/AK74 Rifle
* AK74 Modified Rifle
* RPK Automatic Rifle
* Mosin-Nagant Sniper Rifle
* SVD Sniper Rifle
* Vintorez Sniper Rifle
* RPG-7 Rocket Launcher

### Opfor Vehicles

* T-62
* BTR Troop transport (APC)
* BMP Infantry Fighting Vehicle

### Grenades

* Frag Grenade
* Smoke Grenade
* Flash Grenade
* Incendiary Grenade

## Game Rules and Regulations

* The RoE and Rules
* Honor Scale
* Player Rankings
* Cheat Detection

## Misc

* Tweaks
* Console Scripting
* Common Issues
* The Future of AA
* Lore
* TacticalMaps

## Community

* Teams/Clans
* Links of Interest
* Contributors
* Interviews
# America's Army: Special Forces/AK47/AK74 Rifle

See also: AK-47
The AK-47 is the Opfor weapon equivalent to the M16A2.
It has some diffrences than to M16 Becase it is Fully Auto and Packs More Of a Punch. But you do have to kill an opfor to get it.
# America's Army: Special Forces/Basic Marksmanship Training
## Basic Marksmanship Training

* Use Iron Sights: Always use iron sights. This is the way to line up your shot properly. It increases your combat effectiveness and consequently your likely-hood to hit the target.
* Breathe: Fire between breathing cycles. You CAN hear the inhaling and exhaling. Your combat effectiveness is highest after you finish inhaling or exhaling. Press the insert key to make the your breathing significantly less.
* Stay Low: Crouch whenever possible. The lower you are, the more accurate your shots will be due to increased combat effectiveness.
* Aim for the Center of Mass: Aim at the center of the target's body. Do not aim for the head. Aim one or two pixels to the left of the iron sight.
* One Target, One Shot: You want to get one target with one shot. If you can pull off getting a target with the 2nd shot - DO IT. But be damn sure you can make it. Do not do this more than once. Remember, you only have 40 bullets for 40 targets. To be given a chance to do the Advanced Marksman training a score of 36 is required, which means you can only miss 4 targets.
* Don't Use Left Mouse Button: Use your Ctrl button to fire, so you don't move your mouse when you click.
* Right Mouse Button: Bind your right mouse button to your sights instead of Z so that you can easily zoom in and out to acquire a target.
* Adjust Your Screen Resolution: Put you screen at the lowest resolution possible, so the targets will be a little bigger and easier to hit.
* Press the "SHIFT" key to reduce your walking speed. This puts accuracy up quite a bit.
# America's Army: Special Forces/AT4 Anti-tank Launcher

The M136 AT4 BDM is the Army's primary light antitank weapon. It is a recoilless rocket launcher used primarily by infantry forces for engagement and defeat of armor threats. The design permits accurate delivery of a 84 mm High Explosive Anti-Tank (HEAT) warhead providing excellent penetration capability and lethal after-armor effects.
The system weighs approximately 15 lbs and is man-portable. The AT4 system consists of a free flight, fin-stabilized, rocket packed in an expendable, one-piece, fiberglass-wrapped tube. The launcher is watertight for ease of transportation and storage. The M136 AT4's warhead uses an extremely destructive, 440-gram shaped-charge explosive that can penetrate more than 14 inches (35.6 cm) of armor.
It is a single shot, disposable munition that is usually used to destroy walls, gates, and Strykers. Tests have shown that this will function the same as the RPG, except it will have a larger blast radius and cannot be reloaded. Info subject to change. --Desertfox 59 19:36, 2 May 2004 (UTC)
In game, the AT4 will take two (2) shots to destroy the OpFor Stryker. ~ETG
It has adjustable ironsights for ranges of 100, 200, 300, 400, 500 meters. The default button for this is the mousewheel.
{FoM}Gurkbuster