The document summarizes the history of nuclear weapons, including their effects and key events. It describes the atomic bombings of Hiroshima and Nagasaki by the United States in August 1945, which represented the first and only use of nuclear weapons in warfare. Over 200,000 people were killed in the initial months after the bombings from injuries and radiation sickness. The bombings contributed to Japan's surrender and the end of World War II, though their justification remains debated.

1. Nuclear War
By
Have Fun

2. Introduction
 A nuclear explosion is an explosion that occurs as a result of
the rapid release of energy from a high-speed nuclear
reaction.
 The driving reaction may be nuclear fission, nuclear fusion or
a multistage cascading combination of the two, though to
date all fusion based weapons have used a fission device to
initiate fusion, and a pure fusion weapon remains a
hypothetical device.

3. History
 The atomic bombings of the cities of Hiroshima and Nagasaki in Japan were
conducted by the United States during the final stages of World War II in August
1945. The two bombings were the first and remain the only use of Nuclear
weapons in warfare.
 In 1963, the United States, Soviet union, and United Kingdom signed the Limited
Test ban treaty, pledging to refrain from testing nuclear weapons in the
atmosphere, underwater, or in outer space. The treaty permitted underground
tests. Many other non-nuclear nations acceded to the Treaty following its entry
into force; however, three nuclear weapons states have not acceded: France,
China, and North Korea.
 Nuclear Weapons are the most destructive weapons ever made. Building a
Nuclear weapon was a top secret project during world war II.

4. Nuclear Weapons
 The Tsar bomba
Tsar Bomba (Tsar being derived from Caesar) is the nickname for the AN602
hydrogen bomb, the most powerful nuclear weapon ever detonated. Its October 30,
1961 test remains the most powerful artificial explosion in human history, the bomb
had the yield of 50 to 58 megatons of TNT (210 to 240 PJ). Only one bomb of this
type was ever officially built and it was tested on October 30, 1961, in the Novaya
Zemlya archipelago, at Sukhoy Nos.

5.  Little Boy
Little Boy was the codename for the type of atomic bomb dropped on the
Japanese city of Hiroshima on August 6, 1945 by the Boeing B-29 Superfortress Enola
Gay, piloted by Colonel Paul W. Tibbets, Jr., commander of the 509th Composite
Group of the United States Army Air Forces. It was the first atomic bomb to be used in
warfare. The Hiroshima bombing was the second artificial nuclear explosion in history,
after the Trinity test, and the first uranium-based detonation. Approximately 600 to
860 milligrams (9.3 to 13.3 grains) of matter in the bomb was converted into the
energy of heat and radiation. It exploded with an energy of 16 kilotons of TNT (67 TJ).

6.  Fat Man
"Fat Man" was the codename for the type of atomic bomb that was detonated over
the Japanese city of Nagasaki by the United States on 9 August 1945. It was the
second of only two nuclear weapons ever used in warfare, the first being Little Boy,
and its detonation caused the third man-made nuclear explosion. It was dropped from
the Boeing B-29 Superfortress Bockscar, named after its pilot, Captain Frederick C.
Bock. For the Fat Man mission, Bockscar was piloted by Major Charles W. Sweeney.

7. Effects Of Nuclear Explosions
The energy released from a nuclear weapon detonated in the
troposphere can be divided into four basic categories:
 Blast—40–50% of total energy
 Thermal Radiation —30–50% of total energy
 Ionizing radiation—5% of total energy (more in a neutron bomb)
 Residual radiation—5–10% of total energy with the mass of the
explosion
 There are Direct and Indirect Effects

8. Direct Effects
 Blast Damage:-
The high temperatures and radiation cause gas to move outward radially in a thin,
dense shell called "the hydrodynamic front". The front acts like a piston that pushes
against and compresses the surrounding medium to make a spherically expanding
shock wave. At first, this shock wave is inside the surface of the developing fireball,
which is created in a volume of air heated by the explosion's "soft" X-rays. However,
within a fraction of a second the dense shock front obscures the fireball, and
continues to move past it, now expanding outwards, free from the fireball, causing
the characteristic double pulse of light seen from a nuclear detonation, with the dip
causing the double pulse due to the shock wave–fireball interaction. It is this unique
feature of nuclear explosions that is exploited when verifying that an atmospheric
nuclear explosion has occurred and not simply a large conventional explosion, with
radiometer instruments known as Bhangmeters capable of determining the nature of
explosions.

9.  Thermal Radiation:-
Nuclear weapons emits large amounts of thermal radiation as visible, infrared,
and ultraviolet light, to which the atmosphere is largely transparent. This is known
as "Flash“ . The chief hazards are burns and eye injuries. On clear days, these
injuries can occur well beyond blast ranges, depending on weapon yield. Fires
may also be started by the initial thermal radiation, but the following high winds
due to the blast wave may put out almost all such fires, unless the yield is very
high, where the range of thermal effects vastly out ranges blast effects, like that
observed in the multi-megaton range. This is because the intensity of the blast
effects drops off with the third power of distance from the explosion, while the
intensity of radiation effects drops off with the second power of distance. This
results in the range of thermal effects increasing markedly more than blast range
as higher and higher device yields are detonated. Thermal radiation accounts for
between 35-45% of the energy released in the explosion, depending on the yield
of the device.

10. Indirect Effects
 Electromagnetic pulse:-
Gamma rays from a nuclear explosion produce high energy electrons through
Compton scattering. For high altitude nuclear explosions, these electrons are
captured in the Earth's magnetic field at altitudes between twenty and forty
kilometres where they interact with the Earth's magnetic field to produce a coherent
Nuclear electromagnetic pulse (NEMP) which lasts about one millisecond. Secondary
effects may last for more than a second.
The pulse is powerful enough to cause moderately long metal objects (such as
cables) to act as antennas and generate high voltages due to interactions with the
electromagnetic pulse. These voltages can destroy unshielded electronics. There are
no known biological effects of EMP. The ionized air also disrupts radio traffic that
would normally bounce off the ionosphere.

11.  Ionizing Radiation:-
About 5% of the energy released in a nuclear air burst is in the form of ionizing radiation:
neutrons, gamma rays, alpha particles and electrons moving at speeds up to the speed
of light. Gamma rays are high energy electromagnetic radiation; the others are particles
that move slower than light. The neutrons result almost exclusively from the fission and
fusion reactions, while the initial gamma radiation includes that arising from these
reactions as well as that resulting from the decay of short-lived fission products.
The intensity of initial nuclear radiation decreases rapidly with distance from the point of
burst because the radiation spreads over a larger area as it travels away from the
explosion (the inverse squared law). It is also reduced by atmospheric absorption and
scattering.
The character of the radiation received at a given location also varies with distance from
the explosion . Near the point of the explosion, the neutron intensity is greater than the
gamma intensity, but with increasing distance the neutron-gamma ratio decreases.
Ultimately, the neutron component of initial radiation becomes negligible in comparison
with the gamma component. The range for significant levels of initial radiation does not
increase markedly with weapon yield and, as a result, the initial radiation becomes less of
a hazard with increasing yield.

12. Atomic bombings of Hiroshima and Nagasaki
 The atomic bombings of the cities of Hiroshima and Nagasaki in Japan were
conducted by the United States during the final stages of World War II in
August 1945. The two bombings were the first and remain the only use of
nuclear weapons in warfare.
 Late in the war the Allies had begun to prepare for a costly invasion of Japan,
to follow the firebombing campaign that destroyed many Japanese cities. The
war in Europe ended when Nazi Germany signed its instrument of surrender
on May 8, 1945, but the Pacific War continued. Together with the United
Kingdom and China, the United States called for the unconditional surrender
of the Japanese armed forces in the Potsdam Declaration on July 26, 1945,
threatening "prompt and utter destruction".

13.  By August 1945, the Allied Manhattan Project had successfully
tested an atomic device and had produced weapons based on two
alternate designs. A uranium gun-type atomic bomb (Little Boy) was
dropped on Hiroshima on August 6, 1945, followed by a plutonium
implosion-type bomb (Fat Man) on the city of Nagasaki on August
9. Within the first two to four months of the bombings, the acute
effects killed 90,000–166,000 people in Hiroshima and 60,000–
80,000 in Nagasaki; roughly half of the deaths in each city occurred
on the first day. During the following months, large numbers died
from the effect of burns, radiation sickness, and other injuries,
compounded by illness. In both cities, most of the dead were
civilians, although Hiroshima had a sizeable garrison.

15.  America dropped the nuclear bomb to end the world war quickly when
Japan failed to surrender .
 The Aftermath of the attack was Horrible the whole country had fell on its
knees and even now the to this day it is still causing damage to the
people.
 On August 15, just days after the bombing of Nagasaki and the Soviet
Union's declaration of war, Japan announced its surrender to the Allies. On
September 2, it signed the instrument of surrender, ending World War II.
The bombings' role in Japan's surrender and their ethical justification are
still debated.
 Long after that a documentary was released documenting the aftermath of
the attack and documenting everything that went on behind Americas
attack to the situation of people including children was released

16.  Today the United States and Japan have firm and very active political,
economic and military relationships. The United States considers Japan to
be one of its closest allies and partners . Japan is one of the most pro-
American nations in the world, with 85% of Japanese people viewing the
U.S. and 87% viewing Americans favourably in 2011, 73% of Japanese
people viewing Americans favourably and 69% of Japanese people viewing
the U.S. favourably in 2013, going down somewhat to 66% in 2014. and
most Americans generally perceive Japan positively, with 81% viewing
Japan favourably in 2013, the most favourable perception of Japan in the
world, after Indonesia.

17. Conclusion
 At the moment almost every country has added Nuclear weapons to their Arsenal
and are equipped with high technology Next-Gen weapons in order to protect and
defend themselves from enemies and other attacks.
 However the case, it is not possible to understand if any more current studies are
going on related to this field. It is most probably be going on and if it is then it is
definitely considered as classified and top secret.
 Lets just Hope that we would never have to use this deadly weapon against any
country ever in the course of human existence, because the disadvantages of
nuclear weapons are extremely high and it outnumbers the advantages of this
horrible weapon in the blink of an eye.

18. THE END