Saturday, August 30, 2008

Rain (The Poem)

Note from mum: This is a poem by Jack. He suddenly wrote it and emailed it to me. I thought it's nice to publish it.... (mum)
Rain
Rain is pouring,
Outside my window
I can feel Rain,
As I can feel my heart beat
Rain is inspiring,
As it is pointless,
Though it must:
Water those who are in need

Before the men,
Before the women,
Before the children,
Before the animals,
Before the vegetation
Rain is there.

Water becomes rain;
Water feeds those in thirst
Water cools,
The world it is on,
Rain comes from water,
From the clouds
Rain drops,
Pouring on to the world:
Rain.

Monday, August 25, 2008

Independent Boy

Jack is now capable of ironing his own clothes - trousers and shirts. I am not the only who is proud of him. He is too.

Why? Because that is one step of becoming independent. He is only 11, yet he cooks, he washes dishes, and now he can iron his own clothes.

I know too many kids - boys and girls - and grown ups who cannot do these simple things on their own. I just don't agree with mothers - and nannies and cleaners - who spoilts their kids to become dependent unmature people.

I taught Jack to do a lot of stuff while he is young, while I still can supervise him in some ways. Hopefully, these habits of doing things on his own become a life time habit. At least when Jack is 18 and living on his own in a student hall or wherever in the world, he will confidently take care of himself. (and this quality will attract girls too! so I told him)

Well done son. Hope you will do good in your life...

Sunday, June 22, 2008

A Brief History on World War II

Note: Jack has been learning about WW2 at school. So he wrote this on his own (this is not an assignment from any of us nor it is from his school). I guess this is the time when 11-year-old Jack starts educating his mum, because I did not learn this part of the history. My history lessons about WW2 was about the Pacific side - our vilain was the Japanese not the Germans. Well done son!

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World War II was a violent war between the Axis powers and the Allies. All across the world there were numerous battles and fights which brought many deaths and chaos.


The Axis powers
The Axis powers (sometimes known as the Axis alliance, Axis nations, axis countries or just the Axis) were basically countries that approved of administrating the world. The three major Axis powers, Fascist Italy, Nazi Germany and Imperial Japan, enrolled a military alliance to sign the Tripartite Pact, which originated their powers. People, of all varieties, were assassinated by the Axis armies, navies and air forces. Britain fought Germany and Italy, mostly in the air, in the Battle of Britain. Meanwhile, Japan fought the United States, alongside China, the United Kingdom, British India, Australia and Soviet Union, in the Pacific Wars.


The Allies
(Three of the central allied leader: Winston Churchill, Franklin D. Roosevelt and Joseph Stalin)

The Allies were countries who officially opposed to the Axis powers; the British Empire, the Soviet Union and the U.S.A were commonly known as ‘The Big Three’. Before France’s defeat in 1940, they were a major ally, though Poland’s dedications were, in fact, larger. Many countries fought for the Allies although some stayed neutral as time progressed.


The French Resistance

(Croix de Lorraine)



The French Resistance is a resistance movement who fought, mostly in France, the Germans and the Vichy Regime during World War II. Resistance groups consisted armed men and women of all ages, occupations and religions. Some would publish underground newspapers whilst others discovered secret passages which helped Allied soldiers escape. Their greatly-admired work was a great advantage for the Allies.

Evacuation in Britain
The only citizens who were evacuated to the countryside were children and pregnant women; the reason for this is because children are the future of Britain so you must protect the future. Though, some did stay at their homes as their already-miserable parents couldn’t bear the thought of evacuating their children. All evacuations went smoothly and no one was hurt or killed.

Air raid shelters

The two main shelters in Britain were the Anderson shelters (left) and the Morrison shelters (right). An Anderson shelter was, basically, a deep, dug-up hole covered with an arc of galvanised corrugated steel panels, which was then covered with the left-over earth. Morrison shelters were, oddly enough, tables with steel plate table tops, welded wire mesh sides and a metal ‘mattress’ type floors. Although Anderson shelters were obviously safer and more lives were saved by them, the Morrison shelters still saved many lives. Despite all this if a bomb fell on any of the shelters then the unfortunate people inside would die; shelters only protected people from the blast of bombs.

1939
Hitler invades Poland on Sept. 1st, Britain and France later declared war.
1940
Rationing began in the UK; this was to prevent an unfair share of food.
Churchill becomes the new Prime Minister of Britain.
The British Expeditionary Force were evacuated from Dunkirk, France.
Britain’s victory from the Battle of Britain forces Hitler to postpone his invasion plans.
1941
Operation Barbarossa began in 1941-the invasion of Russia.
The Blitz continued against Britain’s major cities (e.g. Manchester, London and Coventry)
Tobruk, North Africa is taken by the Allies who resisted German attacks.
Pearl Harbor is hit by Japan, the US joins the war.
1942
  • Unfortunately, Singapore falls to Japan in February –around 25 thousand civilians were taken prisoners.
  • Germany suffers a great setback in Stalingrad, Russia and El Alamein, Egypt.
  • In June, American naval victory at the Battle of Midway marks a turning point in the Pacific War.
  • Assassination of Jews began at Auschwitz, Poland.
1943
German surrendering in Stalingrad marks Hitler’s first major defeat.
Allied victory in North Africa enables the invasion of Italy.
Italy surrenders, but Germany takes over.
British and Indian forces battles with Japan in Burma.
1944
The Allies lands at Anzio and bombs monastery in Monte Cassino.
Soviet forces overwhelm Eastern Europe.
D Day: France is invaded by the Allies. Paris is liberated in August.
Guam gets liberated by the US Okinawa, and Iwo Jima gets bombed.
1945
Soviet troops liberate Auschwitz.
Russia reaches Berlin; Hitler committed suicide and the Germans surrendered on May 7th.
Truman replaces Roosevelt as President, whilst Atlee replaces Churchill.
After atomic bombs are dropped on Nagasaki and Hiroshima, Japan surrenders August 4th, 99days after Germany’s surrender.
Despite the vast amount of deaths in World War II, countless survived and some are still here today to tell their extra-ordinary stories.
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Saturday, May 31, 2008

Death in the Grand Plaza

A short story by Jacques Bara

Ms. Davison sat comfortably in her armchair whilst reading an invitation from her old friend, Mrs. Crow. She read it to herself: ‘You, Jane Davison, are invited to a grand luncheon at the Grand Plaza.’ She was to come, as the invitation specifies, to the Grand Plaza, London at noon today. What a coincidence, she thought, as she was planning to go to London, to buy a new party hat. “Juliet?” “Yes, Ms Davison?” “I shall go to London to go to a luncheon and so I shall require my best outfit and shoes, not high heels.”, “Right away my lady.”

“Jane! How are you this fine day?” wondered Mrs. Crow, “Very well actually, Agatha. What a marvellous lounge this is! I see your old habits of pretending to be a hostess has paid off well.”

Wonderfully-crafted teak chairs sat around an onyx-glazed oak table; a magnificent, red rug (originated from China) lay proudly underneath all this. Half an hour later, the clock ticked exactly 12:00pm and suddenly a dozen of Mrs. Crow’s old friends came through the grand, leather-padded oak doors. “Ms. Davison! I am such a fan of your works; ‘The Scorching Desert’ is my personal favourite.” admired Mrs. Brown “The inspiration came from my exhausting trip to India” “Why Ms. Davison what a pleasure, Phillip Brown, teacher of literature. I and my dear wife were only just talking about you and Mrs. Crow, how unfortunate of her not to have any family.” “Yes poor old Agatha, I’m sure she’ll have a backup plan, maybe adoption in which case the child will then become heir to Mrs. Crow’s fortune.”

“Everybody I have some wonderful news to share with you all. For years you have assumed that I have no heir to my family fortunes when actually she has been living quietly with me in secret. It’s my pleasure to present you Jane Crow; I adopted her as soon as she was born, in Manchester, so I had the pleasure of picking a name for her, I chose Jane Crow after my dearest friend, Ms. Davison.” Gasps and claps filled the lounge as a beautiful girl walked inside; blonde, mid-30 and a great personality. “Why have you kept her this long from us, Agatha? A sense of guilt, maybe? Or was it her choice?” enquired Vicar Whals who was wearing, what seems to be, a ruby necklace with a hint of pink. “I hid her because I did not think the time was right to present her to you. In addition to this, the father mysteriously disappeared after he gave Jane this precious rose quartz necklace and gone to the cathedral, whilst her mother got killed in a car accident just a mile from the hospital Jane was born in.”

After greeting everyone, Jane quickly favoured Ms. Davison as she was not as boring as the rest of the crowd. Ms. Davison told Jane of her almost-impossible adventures in foreign countries. She also told Jane how she solved many murders and helped to track many criminals and murderers; only Mrs. Crow and Jane Crow, now, knew about this.

Grey, dull clouds suddenly formed in the sky above the Grand Plaza. “Oh bother and blast! Well, we shall eat even in the midst of this appalling weather.” Ms. Crow clapped to signal the servants to bring out the well-cooked lobsters surrounded bye crispy salad and delicious mussels. Ms. Davison had no idea it was lobster; she absolutely adores lobster, especially with mussels. Sadly not all the guests were there, Mr and Mrs Brown and Vicar Whals were three of them, so they could not start. Out of the blue, the magnificent stained windows broke and a dark, mysterious figure was highlighted from the lightning and the sound of a gunshot whilst a scream of help echoed as one guest fell silently towards her right and then to the floor…

“Ms. Jones! How miserable must her fiancĂ© be? And only just a week until the wedding in Portsmouth! Why her, Lord?” gasped Ms. Foster as she dumb-wittedly dropped her champagne on to the blood stained rug near the victim.

An hour later, the police from Scotland Yard came and taped off the whole lounge; only police and Ms. Davison were allowed inside. The body was immediately brought to hospital for signs of the murder weapon. “Time of death,” announced chief inspector Mason, “12:21pm. A clock mysteriously broke, somehow.” “Odd how she fell to her left rather to her right when the window, the murderer broke through, was more to her right,” wondered Ms. Davison, “bring in the people who were not in the room at that point, chief. I think I shall question Mrs. Brown first.” “Very well Jane. Bring in Mrs. Brown!”

“Where were you at the time of the death?” “Why I was only on my way back from the cloak room,” replied Mrs. Brown, “I forgot my cigars. Oh did I just say that? Please don’t mention this to my husband. He’s so fussy about the cigars killing me! Load of poppycock if you ask me.” “Did you see or hear any mysterious sounds on your way back?” “Now that you mention it, I did hear a loud thump above me. Rubber-boots it sounded like.” “Yes, rubber-boots explains how he or she climbed down to the window.” “Are you right-handed or left-handed?” “Right-handed. Well I hope I’ve been of good use to you, Ms. Davison.”

“Where was I at the time of death? I was exploring the library; searching for my works and trying to see whether Agatha was a fan. It’s quite a prestigious thing to find out who one’s fan is and who is not,” replied Mr. Brown “Yes quite. Did you see anything at all?” “I did see a rather suspicious light, though not as bright, I still thought it was the odd lightning.” “Are you right-handed or left-handed?” “Left-handed.”

“Ms. Crawford, I don’t recall ever meeting you,” “Yes that’s because I came here to see Mr. Brown, he has financial issues; I’m from the insurance company and about to fine him as he did not pay his insurance over the month.” “, ah I see. Now back to my enquiry; where were you at the time of murder?” “I was on my way to the library when I suddenly heard the smash and the scream. I did see a figure walking to the hallway window with some sort of reflecting object in his left hand.” “Yes! Yes! That’s it! Thank you very much Ms. Crawford. Two last questions: did you see Mr. Brown in the library? Are you right-handed or left-handed?” “Yes and I’m left-handed.”

“I was at the loo when I heard a fuss; I panicked and accidentally dropped my precious jewellery box!” “Did you pick it up, Mrs. Anderson?” “I was planning to pick it up but when I got outside, a quarter of an hour ago, it seemed to disappear!” “Did you see or hear anything else?” “Um… I don’t remember.” “Out of interest, what is your occupation at the moment?” “I’m a professional knitter.” “Are you right-handed or left-handed?” “Both, a knitter has to be skilled in both hands to achieve high quality.”

“I was in the bedroom in between the bathroom and library. I accidentally left some of my belongings there from a week ago.” “Were you by yourself?” “One is never quite alone; God is always in our hearts.” “Are you right-handed or left-handed?” “Left, but I don’t know how that helps.” “It does Vicar, it does.”

Now inside the bedroom that was said to have the Vicar in it last week, Ms. Davison and chief inspector Mason searched every crack and corner for any clues. Then she stopped to look at the painting on the wall separating this room and the bathroom. Funny picture, a sailor on a boat hauling some rope (seems to be 2cm thick) towards Ms. Davison. “That’s it! Chief, please take this painting from the wall.” As soon as the painting came off, a hole was discovered, behind the painting, and about 2cm thick.

All the guests were ordered to come in to the lounge. “Everyone I have some prestigious…” A gunshot, a scream for help, a loud thud and Mr. Brown was dead…

“Phillip! No! Why Phillip?!” sobbed Mrs. Brown affectionately at the dead, old man, “Yes why Mr. Brown?” Suddenly Ms. Davison saw a piece of parchment, dropped by Mr. Brown, in the corner of her eye. “Father…father!” a bright smirk came over Ms. Davison’s face. “Father?” wondered the guests

“Two murders! Poor Ms. Jones and dear old Mr. Brown. Why? Why play this cruel game on these poor people?” “I’m not sure Ms. Jones never was meant to die; she had no financial issues, much money and there were no other signs why she should die.” Explained Ms. Davison, “You’re saying that it was not on purpose?!” “Yes, and now I’m ever so sure of the murderer’s plans and who they are.”

“Agatha Crow, you adopted Jane from a couple who died a few hours after the birth. Unfortunately you never knew the parents names, so the birth certificate was never specific. Of course the father never wanted to give his daughter to some stranger; it was the mother’s decision. In which case the father then decided to go on a drive to somewhere, the mother followed suit to find her frustrated husband. They met each other on a crossing near a cathedral; frustrated by the loss of his daughter, the father crashes the car at a tremendous speed at the mother’s car and killed her in the process. Despite killing his wife the father survived with a severe injury, a mental health problem, but there was hope; the local bishop heard the crash so instinctively came out to see what’s happened. He finds the father and takes him into care; the father stayed with the bishop and learnt the wonders of being a Roman Catholic.”

“Thirty-four years later the father, now a vicar, had managed to track down his daughter and so he comes here. Of course he came here to see his daughter but then had an idea; if he killed Agatha then he can adopt his daughter and eventually tell her the truth. So he decided to kill Agatha from the window. His plans were ruined by the thunder storm, he could not go out otherwise he would leave unmistakable foot-prints. But then he remembered that an old friend of his was here, and she was a professional knitter.

They talked to each other and made an agreement: if she provided him with rope, he would give her a quarter of the money that Jane will receive as she is heir to Agatha’s money. As she was about to give him the rope, they heard footsteps. He came into the bedroom he was in last week whilst she went into the bathroom. The painting was removed and the rope was exchanged through the hole behind the painting. Quickly he ran to the hall window, just above the lounge window, and climbed down it. Before he broke in, Vicar Whals was handed the murder weapon, a dagger, from Mrs. Anderson. The Vicar broke in, shot the clock with his shotgun and then threw his dagger at Agatha. Fortunately he missed but hit Ms. Jones, just on the left of Agatha, she fell towards her left because she was hit on her right and also the Vicar is left-handed. Am I correct Vicar Whals, or should I say Thomas Walsh?”

“Damn you Ms. Davison, every bit of detail was correct! Go on then, arrest me, but don’t forget Mrs. Anderson, she helped and she knew what she was in to.”

Applauds and cheers echoed around the scene-of-the-crime (the lounge). “But there’s more, you see Mr. Brown figured this out and found the last piece of evidence he needed to support his idea. That’s where this piece of parchments comes in, ‘Father’ it says, meaning the father of Jane Crow. Sadly the Vicar found out about this and when his chance arrived, last time we gathered in here, and shot Mr. Brown with the shotgun.”

After the police of Scotland Yard came and took Vicar Whals and Mrs. Anderson to jail, the guests finally could eat their fresh, newly-cooked lobsters with muscles. Ms. Davison enjoyed every bit of it and ended the meal by singing a gay, hysterical song she completely made up about mussels and lobsters singing and dancing.

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Sekretaris Jenderal PBB Menolong kelaparan

Kemiskinan Makanan
  • Ada 854 juta orang yang tidak punya cukup makanan, dari 852 juta di tahun lalu.

  • Setiap hari, hampir 16 ribu anak-anak yang mati karena sebab-kelaparan; satu anak setiap 5 detik. Terus juga ada 2112 juta anak yang dihitungkan di 2007, jadi ada 0.000757576% yang mati setiap hari karena kelaparan. Jadi kalau anak-anak cuman mati karena laparan dan ibu-ibu tidak punya bayi dalam 132000 hari semua anak-anak akan mati.

  • Karena jalan-jalannya Irak menjadi medan perang, banyak warganegara Irak menjadi tawanan di rumahnya sendiri dan jadi makin lapar, ibu-ibu juga punya banyak kesempatan akan punya bayi mereka di rumah.

  • Harga makanan yang meningkat dari tahun lalu menjadi salah satu masalah besar untuk PBB memecahkan sampai 2015. Tetapi masih ada masalah-masalah yang masih belum selesai di dunia ini.

  • 4 juta orang di UK(6.66666667% atau 1/15) tidak bisa membeli makanan yang cukup untuk kesehatan; 1 dari 7 orang-orang pada umur dari 65 tahun punya risiko mendapat kekurangan gizi.

  • Salah satu masalah yang menghasilkan kemiskinan makanan adalah harga-harga bertambah terlalu banyak dari tahun lalu.
Karena hampir ada 854 juta, dari kelaparan, mati setiap hari di seluruh dunia, aku pertama coba untuk memecahkan soal berat ini di negara-negara yang di mempengaruhi paling banyak. Aku tahu anak-anak Irak mati karena mereka terjebak di rumah mereka dan juga bahwa banyak anak-anak tidak bisa membeli cukup makanan karena harganya terlalu mahal. Ada juga yang tidak punya banyak panen, pertolongan dan persediaan, seperti di Afrika. Jadi aku pertama memberikan Afrika ayir bersih untuk selama aku bisa, terus aku impor sapi dan ayam ke tempat tertentu seperti Zimbabwe dan Afrika Selatan. Kemudian aku mengirimkan beberapa tentara, yang sudah di Irak, dari Britania ke rumah-rumah, yang di mengilingi bagi bertempuran, untuk memberi makanan dan air ke orang-orang yang tinggal di dalam. Juga doktor-doktor yang selalu siap untuk menolongi ibu-ibu yang akan punya bayi.

Indonesia
Aku terus ke Indonesia untuk belajarin kenapa orang-orang Indonesia menanggulangi kesulitan-kesulitan kelaparan dan bagaimana aku bisa menhalangi kelaparan. Hasi-hasil ini mungkin karena sedikit hasil panennya Aceh dan Papua diberikan ke seluruh Indonesia jadi Aceh dan Papua punya lebih sedikit makanan dari panen-panen. Jadi pemecahanku adalah untuk Aceh dan Papua, kalau tidak menjadi negara sendiri, tidak harus memberikan panen-panenya ke kota-kota yang lain. Soalnya kalau terus memberikan panenya ke kota yang lain, nanti Aceh dan Papua tidak akan punya cukup makanan untuk semua orang-orang yang bertempat disana akan mati karena tidak punya cukup makanan.

India

Sekarang aku ke India untuk mencoba menhalangi kelaparan anak-anak yang di sekolah mereka dan di rumah mereka dan orang-orang tua. Meskipun pemerintah janjikan makanan yang punya cukup bahan gizi untuk anak-anak yang masih bertumbuh, makanan lengkap masih tidak di diberikan anak-anaknya India. Jadi aku perintahi pemerintah untuk bagikan sedikit hasilan panen ke anak-anak dan orang tua yang tidak bisa hidup sendiri, kalau tidak persedian sebagian pesawat dan senjata untuk India akan berhenti.

Korea Utara
Di Korea Utara aku belajar bahwa 65,000,000 orang dari 23 juta tidak punya cukup untuk di makan. Itu dekat 1/3 dari semua penduduk Korea Utara, kalau mau lebih tentu itu adalah 1/3.53846154 atau 28.2608696%. Salah satu hal yang menciptakan masalah ini adalah karena panen-panen tahun ini di meramalkan akan gagal karena banjiran-banjiran berat yang terjadi tahun lalu. Jadi aku bagikan bagian panennya Amerika ke Kore Utara. Aku pilih Amerika karena mereka udah punya banyak makanan dan (aku benaran berpikir) karena ada banyak orang Amerika yang terlalu gendut, karena mereka rakus dan pelit, mereka juga pikir mereka paling hebat.
Thailand
Sekalipun kemiskinan sudah menurunkan dari 48 tahun lalu, pendapatan penyaluran menjadi lebih buruk. Meskipun ada fakta-fakta yang membuktikan bahwa standar kehidupan di Thailand sudah dengan cepat bertambah baik untuk orang-orang Thai, masih ada banyak orang-orang miskin, terutama di utara-timur Thailand. Jadi aku pilihkan orang-orang yang mau bekerja untuk PBB dan menolong sebagian orang-orang Thai untuk membirikan makanan dan persediaan ke semua orang-orang yang tidak dapat cukup makanan. Dan juga satu sukarelawan dari PBB untuk memeriksakan kalau pemerintah bertolongi orang-orang Thai.
UK

Paling terakhir adalah UK. Meskipun tidak kelihatanya punya masalah makanan, 4 juta orang-orang di UK(6.66666667% atau 1/15) tidak bisa membeli pangah yang teratur. Jadi karena harga makanan terlalu mahal, aku akan mengurangi harganya makanan bagai 15% untuk semua negara-negara, tetapi Afrika yang aku akan menurungkan bagai 19%, supaya mereka tidak punya masalah ini juga.

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Tuesday, April 22, 2008

If I were the UN Secretary General

Note from mum: This week's assignment came from family friend Binny Buchori who was staying with us for a couple of days. Jack should imagine being the secretary general of the UN and write what he would do to solve the problem of hunger/famine in the worl. BUT.. he has to write this 5 pages essay in Indonesian language ("Bahasa Indonesia"). We were concern that Jack is loosing his ability to speak, read and write in Indonesian Language and decide that he should re-learn it because one day being bi-lingual will be his asset. We all are looking forward to reading Jack's essay in Indonesia (and then we shall ask him to make a summary in English)

Sunday, March 30, 2008

Basic Quantum Physics for 9 year olds

Note from mum: Jack has been saying to everyone that he wants to be a quantum physics scientist. So this week's assignment is a preparation to his ambitious dream. Frist Jack had to try to understand the basic concept of the subject. Then he has to explain it to a pupil 2 years younger than him (9-year-old). So he needs to explain the subject in simple sentences. Andy specified that Jack should not use words more than 3 syllables unless it is a name. Any difficult terminology should be explained in a bracket with in a simple sentence.
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Basic Quantum Physics for 9 year olds






The Big Bang

The Big Bang happened from the remains of other universes which were destroyed by a black hole. According to the Big Bang model, the universe grew from an extremely dense and hot state and still grows today. A common and useful resemblance explains that space is expanding, carrying galaxies with it, like raisins in a rising loaf of bread. Just after a few bits of a second after the Big Bang, quarks and gluons roamed free in a blazing hot jumble of mater: a quark-gluon plasma. But then the plasma quickly cooled, and the quarks and gluon formed more familiar particles such as neutrons and protons which the formed atoms. The quark-gluon plasma reduced and disappeared. The universe was just too cool for the quark-gluon plasma, just as the Earths surface is too cool for a puddle of molten iron.

Particle Accelerators
Scientists have begun to re-create the conditions of the first few bits of a second of the universe. They did this by speeding up heavy nuclei (plural nucleus which is the centre of a particle) at 99.99% of the speed of light and slamming them together. This is achieved by a machine called a particle accelerator(a machine which speeds up particles); CERN’s, a french group of scientists based in Geneva, old accelerator is called the LEP, Large Electron-Proton Collider, which is now being replaced by the LHC, Large Hadron Collider, due to open in late May 2008.

Sub-Atomic Particles
Before we begin, a sub-atomic particle is a particle which either forms an atom or is smaller than one. All of matter is made from atoms which in turn are made from protons, neutrons and electrons. The proton and electron have a positive charge whilst the Neutron has a negative charge. A proton or a neutron are usually the nucleus of an atom and so are classed as nucleons, particles which forms the nucleus of an atom. An electron shell is either a group of electrons or, very rarely, an electron, which orbits and determines what element that atom creates. The number of protons and neutrons also determine the element.

Nuclear Weapons
The nuclear weapon we are going to look at produces their explosive energy, which makes them explode, through nuclear fission alone. These are known as atomic bombs, A-bomb or fission bombs. In fission weapons, a group of fissile (improved uranium or plutonium) is gathered into a supercritical mass, the amount of material needed to start a growing nuclear chain reaction, either by shooting one piece of material into another (known as the "gun" method), or by compressing a sphere of material using explosive chemicals to many times its original density (the "implosion" method).