OpenLLM-France/wikimedia huggingface dataset:
# Electronics/Expanded Edition Resonance

< Expanded Edition

## Resonance

Simple resonant circuit, description.

## Filters
### Ideal Filters

(Discussion of how ideal filters provide the signal until the break frequency/cies and then provide total attenuation. That is they look like a $u(\omega )-uu(\omega -\omega _{c})$ for low pass filter, where u(w) is the unit step function or Heaviside function. That is they have infinite drop off at the cutoff frequency. How this is not possible. Pretty diagrams of all the filters Low Pass, High Pass, Band Pass, Band Stop.)
This section introduces first order butterworth low pass and high pass filters. An understanding of Laplace Transforms or at least Laplace Transforms of capacitors, inductors and resistors.

### Low Pass

Transforming the Resistor and Capacitor to the Laplace domain we get:
    R and ${\frac {1}{Cs}}$.
Expressing $V_{out}(s)$ using terms of $V_{in}(s)$.
    $V_{out}(s)={\frac {V_{in}(s){\frac {1}{Cs}}}{R+{\frac {1}{Cs}}}}$
    $V_{out}(s)={\frac {V_{in}(s)}{RCs+1}}$
The transfer function is
    $H(s)={\frac {V_{out}(s)}{V_{in}(s)}}$
So
    $H(s)={\frac {1}{RCs+1}}$
For the Frequency Domain we put $s=j\omega$
    $H(\omega )={\frac {1}{jRC\omega +1}}$
The magnitude is
    $|H(\omega )|={\frac {1}{\sqrt {R^{2}C^{2}\omega ^{2}+1}}}$
and the angle is
    $<H(\omega )=-arctan(RC\omega )\,$
As $\omega$ increases $|H(j\omega )|$ decreases so this circuit must represent low pass filter.
Using the -3 dB definition of band width. $|H(j\omega )|={\frac {1}{\sqrt {2}}}$
    ${\frac {1}{\sqrt {2}}}={\frac {1}{\sqrt {R^{2}C^{2}\omega ^{2}+1}}}$
Therefore
    $2=R^{2}C^{2}\omega ^{2}+1$
    $\omega ={\frac {1}{RC}}$
Which gives the general form of a low pass butterworth filter as:
    $|H(\omega )|={\frac {1}{\sqrt {1+({\frac {\omega }{\omega _{c}}})^{2k}}}}$
, where k is the order of the filter and $\omega _{c}$ is the cut-off frequency.

### High Pass

    (Image of a first order RL high pass filter)
If all the component of the circuit are transformed into the Laplace Domain. The resistor becomes $R$ and the inductor becomes $Ls$. Using voltage divider rule $H(s)$ below is reached.
    $H(s)={\frac {\frac {Rs}{L}}{1+{\frac {Rs}{L}}}}$
If $H(s)$ is transformed into the frequency domain by putting $s=j\omega$.
    $H(\omega )={\frac {\frac {j\omega R}{L}}{1+{\frac {j\omega R}{L}}}}$
Which has a magnitude of
    $|H(\omega )|={\frac {\sqrt {\frac {\omega ^{2}R^{2}}{L^{2}}}}{\sqrt {1+{\frac {\omega R^{2}}{L^{2}}}}}}$
and an angle of
    $<H(\omega )=90-\arctan({\frac {\omega R}{L}})$
    (cut-off frequency is w (R/L)^0.5)
# Electronics/FET
## Field Effect Transistor

The most common transistors today are FETs (Field Effect Transistor). These transistors are characterized as having a conductance between source and drain dependent on the voltage applied between the gate and the source terminals. The dependence is linear if the gate to drain voltage is also high along with the gate to source voltage. It turns into a square-law relationship if the gate to drain voltage is not enough.

## Disadvantages

One of the issues that comes up in circuit design is that as chips get smaller the insulator gets thinner and it starts to look like Swiss cheese. As a result the insulator starts acting like a conductor. This is known as leakage current. One solution is to replace the insulator by a material with a higher dielectric coefficient.
Two types: enhancement and depletion. Enhancement is the standard MOSFET, in which a channel must be induced by applying voltage. Depletion MOSFETs have the channel implanted, and applying voltage causes the channel to cease being conductive.
FET transistors respond to the difference in voltage bias between the gate and the source.
MOSFET (Metal-Oxide-Semiconductor FET): standard FET
JFET (Junction Fet): When voltage is applied between the source and drain current flows. Current only stops flowing when a voltage is applied to the gate.
MESFET (MEtal-Semiconductor FET): p-n junction is replaced with Scottky junction. Not made with Silicon.
HEMT (High Electron Mobility Transfer): A MESFET
PHEMT (Pseudomorphic HEMT):
# Electronics/Expanded Edition DC circuits

< Expanded Edition

## Resistance

Ohm's law, resistivity and conductivity

## Capacitance

Some formulae for capacitance of different shapes, dependence on dielectric constant, units

## Batteries

Behaviour in circuits

## Solving circuits

Kirchoff's laws, Thévenin's theorem

## Hall effect, Piezoelectricity, etc

Voltages induced by magnetic fields, stress, temperature difference, etc.
# Electronics/Expanded Edition Fundamentals

Expanded Edition

## Coulomb's law

Dielectric constant, definition of charge
Electricity
    $F={kq_{1}q_{2} \over r_{2}}$
The force resulting from two nearby charges is equal to k times charge one times charge two divided by the square of the distance between the charges.
    $E={F \over q}$
The electric field created by a charge is equal to the force generated divided by the charge.
    $E={kq \over r_{2}}$
Electric field is equal to a constant, “k”, times the charge divided by the square of the distance between the charge and the point in question.
    $U={(kq_{1}q_{2}) \over r}$
Electric potential energy is equal to a constant, “k” multiplied by the two charges and divided by the distance between the charges.
Variables
F: Force (N) k: a constant, 99 (N•m2/C2) q1: charge one (C) q2: charge two (C) r: distance between the two charges, (m)
A charge in an electrical field feels a force. The charge is not a vector, but force is a vector, and so is the electric field. If a charge is positive, then force and the electric field point in the same direction. If the charge is negative, then the electric field and force vectors point in opposite directions.
A point charge in space causes an electric field. The field is stronger closer to the point and weaker farther away.

## Ampere's law

Definition of current, magnetic permittivity
# Electronics/Formulas

Electronics | Foreword | Basic Electronics | Complex Electronics | Electricity | Machines | History of Electronics | Appendix |

## Conductor's Properties
### Voltage

    $V={\frac {W}{Q}}$

### Current

    $I={\frac {Q}{t}}$

### Energy

    $E={\frac {W}{t}}={\frac {W}{Q}}{\frac {Q}{t}}=V\cdot I$

### Conductance

    $Y={\frac {I}{V}}={\frac {1}{R}}$

### Resistance

    $R={\frac {V}{I}}={\frac {1}{Y}}$

## Resistance and Temperture

Resistance of a conductor increase with increasing temperature

### For Conductor

    R = R$_o$ + N T

### For Semi Conductor

    $R=R_{o}e^{N}T$

## Ohm's Law
### Resistance

    $R={\frac {V}{I}}$

### Voltage

    $V=I\cdot R$

### Current

    $I={\frac {V}{R}}$

### Power

    $P=I\cdot V$

## Power Delivered

Electric Power delivered through resistive network is equal to Electric Power Supply minus Electric Power Loss as Heat through resistance of the resistive network

### Electric Power Supply

    $P_{v}=IV$

### Electric Power Loss

    $P_{r}=I^{2}R={\frac {V^{2}}{R}}$

### Electric Power Delivered

    $P=P_{v}-P_{r}$
    $P=IV-I^{2}R=I(V-IR)$
    $P=IV-{\frac {V^{2}}{R}}=V\left(I-{\frac {V}{R}}\right)$

## Work Done

    $W=P\cdot t$
    $W=F\cdot s$
    $W=F\cdot s\cdot \cos \theta$
# Catalan/Lessons/Introduction
## Introduction

    See also: w:Catalan language
The Catalan language descended from Latin, which the Romans brought to Hispania after the defeat of the Carthaginian army of Hannibal in the Second Punic War. It is closely related to Spanish, French, Italian, and especially Occitan. There are over 7.5 million native Catalan speakers and an additional 3 million non-native speakers. The Catalan language is an eminent poetic language, known for its long and rich poetic tradition. It is the second most widely-spoken language in Spain and enjoys extensive use in culture and art.

## History

Catalan had its first "golden age" in medieval times. It was the language of the Crown of Aragon and, until the 15th century, a key Mediterranean tongue. From the 15th century until 19th, Catalan suffered a long period of relative disuse and decadence that culminated in its first prohibition by Philip V of Spain. Since the 19th century, Catalan has recovered its former status, in spite of suffering a second prohibition in Francoist Spain.

## Extent of the Language

Catalan is currently spoken in Catalonia, Valencia, the Balearic Islands, Andorra, the city of Alghero in Sardinia, Northern Catalonia in France, a region of Aragon known as La Franja de Ponent, and the shire of El Carxe in Murcia.
# Catalan/Numerals
### Numerals i ordinals

| 1 u (un, una) | 1r/1a primer/primera |
| 2 dos (dues) | 2n/2a segon/segona |
| 3 tres | 3r/3a tercer/tercera |
| 4 quatre | 4t/4a quart/quarta |
| 5 cinc | 5è/5a cinquè/cinquena |
| 6 sis | 6è/6a sisè/sisena |
| 7 set | 7è/7a setè/setena |
| 8 vuit | 8è/8a vuitè/vuitena |
| 9 nou | 9è/9a novè/novena |
| 10 deu | 10è/10a desè/desena |
| 11 onze | 11è/11a onzè/onzena |
| 12 dotze | 12è/12a dotzè/dotzena |
| 13 tretze | |
| 14 catorze | |
| 15 quinze | |
| 16 setze | |
| 17 disset | |
| 18 divuit | |
| 19 dinou | |
| 20 vint | |
| 21 vint-i-u ((un, una) | |
| 22 vint-i-dos (dues) | |
| 23 vint-i-tres | |
| 30 trenta | |
| 31 trenta-u (un, una) | |
| 32 trenta-dos (dues) | |
| 40 quaranta | |
| 43 quaranta-tres | |
| 50 cinquanta | |
| 60 seixanta | |
| 70 setanta | |
| 80 vuitanta | |
| 90 noranta | |
| 100 cent | |
| 101 cent u/un/una | |
| 102 cent dos/dues | |
| 110 cent deu | |
| 120 cent vint | |
| 200 dos-cents/dues-centes | |
| 300 tres-cents/tres-centes | |
| 400 quatre-cents/quatre-centes | |
| 500 cinc-cents/cinc-centes | |
| 600 sis-cents/sis-centes | |
| 700 set-cents/set-centes | |
| 800 vuit-cents/vuit-centes | |
| 900 nou-cents/nou-centes | |
| 1000 mil | |
| 2000 dos mil | |
| 100.000 cent mil | |
| 1.000.000 un milió | |
| 2.000.000 dos milions | |
All numbers in a downloadable file for learning with the computer
# Catalan/L005

(Prev) Lesson 5: Al bar - At the bar. (Next) :
| català | English |
| Avui, el Harry és al bar. əbuj, əl (h)ari ez əl bar. | Today, Harry is at the bar. |
| Ell$^1$ espera el seu amic. eʎ əsperə əl sew əmic. | He's waiting (he-waits-for) his friend. |
| Una cervesa, si us plau!$^2$ unə sərbɛzə siwsplaw. | A beer, please! |
| El seu$^3$ amic arriba. əl sew əmic ərribə | His friend arrives. |
| Arribes tard!$^4$ Ja són les$^5$ nou! ərribəs tart! ʒa son ləz nɔw! | You're (you-arrive) late! It's already nine o'clock! (already they-are the nine) |
| Les nou?$^6$ Arribo d'hora! Avui és divendres! ləz nɔw? ərribu dɔrə! əbuj ez dibɛndrəs! | Nine o'clock? I'm early (I-arrive of-hour)! Today is Friday! |
NOTES
1: Pay particular attention to the pronunciation of ell, he. The feminine form is ella. Like jo, I and tu, you they are often unexpressed because the verb tells who is doing the action.
2: si us plau, please is literally if to-you it-pleases. It is a fixed expression pronounced as a single word. 3: Notice the final 'd' in tard is pronounced as 't'. This is a common feature of Catalan.
4: el seu amic, (the) his friend. The feminine form is seva. We have seen teu / teva, your and now seu / seva. his/hers/its.
5: les, the is the plural of la. It used before plural feminine words. See note 6.
6: The time is given as les + number, except for one o'clock which is la una. The les / la refers to omitted word hora, hour.

### Translation Exercise

* La seva dona espera al bar.
* Esperes a casa?
* El Harry espera la seva cervesa.
* L'Anna arriba tard.
* Qui ets? Sóc el teu amic!
# Catalan/Plural

Note the word endings, and how they change in their plural forms:
Words ending in "a" or "e" get an "s". casa-cases, note that the ending "a" always changes to "e" before the "s"
Words ending in "à" - the ending becomes "ans" humà-humans
Words ending in "è" or "é" - the ending becomes "ens" cinquè-cinquens
Words ending in "í" - the ending becomes "ins" camí-camins
Words ending in "ò" or "ó" - the ending becomes "ons" camió-camions
Words ending in "ú" - the ending becomes "uns" oportú-opportuns
Words ending in "s" - the ending becomes "ssos" gos-gossos
Words ending in "ix" - the ending becomes "ixos" baix-baixos
Words ending in "tx" - the ending becomes "txos" esquitx-esquitxos
Words ending in "ig" - the ending becomes "itjos" desig-desitjos
Words ending in "aig" - the ending becomes "ajos" assaig-assajos
And finally, words ending in any other consonant - simply get an extra "s" curt-curts
However, be careful with the following orthographic changes.
-ca becomes -ques vaca-vaques
-ga becomes -gues euga-eugues
-qua becomes -qües Pasqua-Pasqües
-gua becomes -gües aigua-aigües (in order to preserve the [gua] sound
-tja becomes -tges platja-platges
-ça becomes -ces caça-caces
# Catalan/L001

Lesson 1: D'on ets? - Where are you from? (Next) :
| català | English |
| Hola! D'on ets?$^1$ ɔlə! don ets? | Hello! Where are you from? (from-where you-are?) |
| Sóc$^2$ de Barcelona. I tu? sok də bərsəlonə. i tu? | I'm from Barcelona. And you? |
| Jo sóc de Londres. Sóc anglès.$^3$ ʒɔ sok də londrəs. sok ənglɛs | I'm from London. I'm English. |
NOTES
1: ets means you are when speaking informally to peers, family, and children. It is from the verb ser or ésser, to be.
2: sóc means I am and is also from ser or ésser. The word jo, I is usually omitted except for contrast or emphasis.
3: anglès, English (nationality) is the masculine form. Notice stress falls on the last syllable anglès. When the speaker is female, she will say sóc anglesa. Be sure to pronounce è as the sound in the English word pet, the so-called "open e".

### Translation Exercise

* Hola! Ets anglès?
* Ets de Barcelona?
* Jo sóc anglesa, i tu?
* D'on sóc? Sóc de Londres.
* D'on ets tu?
# Catalan/L002

(Prev) Lesson 2: Com et dius? - What's your name? (Next) :
| català | English |
| Bon dia! Com et dius?$^1$ bɔn diə! cɔm ət dius? | Good morning! What's your name? (How yourself you-call?) |
| Em dic$^2$ Joan. I tu, qui ets? əm dik ʒuan. i tu, ki ɛts? | My name is Juan (myself I-call Joan). And you, who are you? |
| Sóc el Harry.$^3$ Sóc anglès. No parlo bé català.$^4$ sok əl (h)ari. sok ənglɛs. no parlu be kətəla | I'm (the) Harry. I'm English. I don't speak Catalan well. (no I-speak well Catalan) |
NOTES
1: et dius means you call yourself. This is called a reflexive verb. It's from the verb dir-se, to call oneself. For now, just remember that et dius needs to stay as one whole unit.
2: em dic means I call myself. This is another form of dir-se but when speaking in the first person.
3: Notice the male speaker says el Harry literally, the Harry. Female speakers will use la, as in sóc la Silva, I am (the) Silva.
4: The letter 'o' in parlo and Joan is pronounced as 'u' when it is not in the stressed syllable.

### Translation Exercise

* Hola! Sóc la Silva. Qui ets?
* Em dic Harry.
* Sóc el Joan. Parlo català.
* Com et dius? Ets de Barcelona?
* No sóc de Barcelona i no parlo bé català.
# Catalan/L003

(Prev) Lesson 3: Com estàs? - How are you? (Next) :
| català | English |
| Hola Harry! Com estàs? ɔlə (h)ari! kɔm əstas? | Hello Harry! How are you? |
| Hola Jordi! Estic molt bé, gràcies.$^1$ ɔlə ʒɔrdi! əstik mol be, grasjəs | Hi Jordi! I'm very well, thanks. |
| Com està la teva$^2$ dona? kɔm əsta lə tevə dɔnə? | How is (the) your wife (woman)? |
| Està malalta,$^3$ és a casa.$^4$ əsta məlaltə, ez‿ə cazə. | She's sick, she's at home. |
NOTES
1: estic means I am but referring to a temporary state. It is from the verb estar to be (temporarily). Also notice that that 't' in molt very is silent.
2: la teva dona (the) your wife. Catalan requires the article la the before the possessive teva your. The masculine form would be el teu marit (the) your husband.
3: malalta refers to la teva dona and is in the feminine form. The masculine form is malalt, with a silent 't'. This pattern of a silent letter becoming sounded in the feminine form will show up many times. 4: és means he/she/it is and is from ser. Notice that when an 's' is between two vowels, as is the case in és a and casa, the 's' turns into a 'z' sound.

### Translation Exercise

* Sóc a casa. Estic malalt.
* Com està el teu marit?
* És de Londres?
* La teva dona és anglesa.
* Com estàs? Estic molt bé.
# Catalan/L004

(Prev) Lesson 4: Al$^1$ cafè - At the café. (Next) :
| català | English |
| El Harry i l'Anna$^2$ són al cafè. əl (h)ari i lanə son əl cəfɛ. | Harry and Anna are at the café. |
| L'Anna encara no parla$^3$ bé català. lanə ənkarə no parlə be kətəla. | Anna doesn't speak Catalan well yet. (yet no she-speaks well Catalan) |
| El Joan arriba.$^4$ əl ʒuan ərribə. | Joan arrives. |
| Hola Joan! Com estàs?$^5$ - Molt bé. ɔlə ʒuan! kɔm əstas? - mol be. | Hey Joan! How are you? - Very well. |
| El Joan diu a l'Anna «Com et dius?» əl ʒuan diu ə lanə «kɔm ət dius?» | Joan says to Anna, "What's your name?" |
| Em dic Anna. No parlo molt bé català. Parles anglès? əm dik anə. no parlu mol be kətəla. parləz‿ənglɛs? | My name is (myself I-call) Anna. I don't speak Catalan very well. Do you speak English? |
| Sí, una$^5$ mica. Vols$^6$ un cafè?$^7$ si, unə mikə. bɔlz‿un kəfɛ? | Yes, a bit. Do you want a coffee? (you-want a coffee?) |
NOTES
1: al, at the, to the is obligatory contraction of a + el. el cafè can mean the café or the coffee. 2: l'Anna, (the) Anna. la obligatorily contracts to l' before a, e, o sounds. More on this later. 3: parla, he/she/it speaks from the verb parlar, to speak. We have seen parlo, I speak. Also in this lesson: parles, you speak, used when addressing friends, peers, or children. 4: The double 'r' as in arriba should be a trilled r sound.
5: una, a,an is used before feminine nouns. un is the masculine form, as in un cafè, a coffee.
6: Catalan, like Spanish, does not distinguish 'b' and 'v'. The sound is closer to 'b'.
7: Notice there is no word like "do" here to ask a question. It's just the statement with a different intonation.

### Translation Exercise

* El Joan parla anglès? Sí, una mica.
* El Joan parla català al cafè.
* Vols un cafè? Sí, gràcies.
* Com està el cafè?
* On és el cafè?
# Catalan/Verbs regulars

Catalan verbs can be tricky to conjugate. Many verbs are irregular, though similarities between three basic groups of verbs do exist and a few ground rules can be made. Verb use in Catalan is similar to French and Spanish but has a few notable exceptions:
* Like Spanish, Catalan regularly uses two past tenses.
** If the action was completed today, or the result of the action is still valid, Catalan uses the pretèrit indefinit
*** Aquest matí hem cantat—We sang this morning. Enguany he visitat les illes balears—This year I visited the Balearic Islands
** If the action was completed before today, or the action clearly occurred only once, Catalan uses the pretèrit perfet
*** Ahir al matí vam cantar—We sang yesterday morning. L'any passat vaig visitar les illes balears—Last year I visited the Balearic Islands
* A third past tense exists, similar to the passé simple in French, the pretèrit perfet simple. Like its French counterpart, it is only used in the more eloquent literary form of Catalan, and it is almost never used in spoken language.
*** El compositor nasqué/naixé l'any 1923—The composer was born in 1923.
TO BE CONTINUED

## External Resources
### Books

* Els verbs catalans conjugats by J.B. Xuriguera (Edicions Claret), a small and comprehensive book outlining the Catalan verb conjugation

### Websites

* Verbix, an online verb conjugator for many languages. Tense, mood, ... names indicated in Catalan
* catalandictionary.org also offer free conjugations of more than 1,000 of the verbs contained in their dictionary, with tenses, mood, ... names indicated in English
* Diccionari normatiu valencià, the AVL's official online dictionary for Valencian with Valencian conjugations for all verbs
# Ruy Lopez: l'Hermet Variation
## Theory table

For explanation of theory tables, see theory table and for notation, see algebraic notation. .
    1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.O-O Nxe4 5.d4 Nd6 6.Bxc6
| 6 |
| Bxc6 ... | = |
| dxc6 ... | = |
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## References

* This Chess related article is a stub. Please assist Wikibooks by expanding it.
# Ruy Lopez:Open Game
## Theory table

For explanation of theory tables, see theory table and for notation, see algebraic notation. .
    1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.O-O Nxe4
| 5 |
| Re1 ... | = |
| d4 ... | = |
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## References

* This Chess related article is a stub. Please assist Wikibooks by expanding it.
# Ruy Lopez:Open Game

Here Black has taken a pawn, but although both black and white have 2 developed pieces, the white rook on f1 and white's queen have more mobility, and white is already castled. Because of white's slight lead in development he is playing d4 to further open the position and make better use of his better development

## Theory table

For explanation of theory tables, see theory table and for notation, see algebraic notation. .
    1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.O-O Nxe4 5.d4
| | 5 | 6 | 7 | 8 |
| | ... Nd6 | Bxc6 dxc6 | dxe5 Nf5 | | += |
| Rio de Janeiro Variation | ... Be7 | Qe2 Nd6 | Bxc6 dxc6 | Nb7 ... | += |
| Transposes to Ruy Lopez Open Defence | ... a6 | Ba4 | = |
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# Ruy Lopez: l'Hermet Variation
## Theory table

For explanation of theory tables, see theory table and for notation, see algebraic notation. .
    1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.O-O Nxe4 5.d4 Nd6 6.Bxc6 dxc6
| 7 |
| dxe5 ... | = |
| Nf5 ... | = |
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## References

* This Chess related article is a stub. Please assist Wikibooks by expanding it.
# Ruy Lopez: l'Hermet Variation
## Theory table

For explanation of theory tables, see theory table and for notation, see algebraic notation. .
    1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.O-O Nxe4 5.d4 Nd6 6.Bxc6 dxc6 7.dxe5
| 7 |
| dxe5 ... | = |
| Nf5 ... | = |
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## References

* This Chess related article is a stub. Please assist Wikibooks by expanding it.
# Ruy Lopez:Open Game
## Theory table

For explanation of theory tables, see theory table and for notation, see algebraic notation. .
    1.e4 e5 2.Nf3 Nc6 3.Bb5 Nf6 4.O-O Nxe4 5. Re1
* 5
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## References

* This Chess related article is a stub. Please assist Wikibooks by expanding it.
# Ruy Lopez: l'Hermet Variation

Named after German chess master and composer Rudolf L'hermet. Moving the knight back while attacking the bishop is the most common continuation of the Ruy Lopez: Berlin Defense among grandmasters.
If 6. dxe5 is played, a common drawing line utilized by top players may arise (see below):
a
b
c
d
e
f
g
h
88
77
66
55
44
33
22
11
a
b
c
d
e
f
g
h
6. dxe5 Nxb5 7. a4 Nbd4 8.Nxd4 Nxd4 9. Qxd4 d5 10. exd6 Qxd6 :
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