Atomic Bomb Meaning, History, Comparison and Importance

Atomic bomb is an explosive weapon that works based on the principle of radioactive fission with release of nuclear energy. The power of atomic bombs is measured in tons equivalent of trinitrotoluene (tons of TNT) [8]. This article discusses atomic bomb meaning, invention, history; comparison, and importance.


-Atomic Bomb Meaning: 6 Different Definitions of the Atomic Bomb

-Atomic Bomb Invention and History

-Atomic Bomb Vs Hydrogen Bomb Comparison

-Importance of Nuclear Weapons like the Atomic Bombs





Atomic Bomb Meaning: 6 Different Definitions of the Atomic Bomb

The atomic bomb is a bomb which is composed of radioactive materials that release large amounts of energy through nuclear fission [14].

An alternative atomic bomb meaning can be given based on the mechanism of energy release from this weapon;

An atomic bomb is a nuclear weapon that derives its power and destructive potential from the splitting of radioactive nuclei and the resultant release of large amounts of nuclear energy.

The following atomic bomb meaning or definition highlights some of the radioactive nuclei that serve as sources of explosive energy;

Atomic bomb is a bomb that releases enormous amounts of energy from fission of the nuclei of heavy radioisotopes like plutonium 239 and uranium 235 [4].

Fission of radioisotopes is an energy conversion process. The atomic bomb meaning can be outlined based on this conversion, as follows;

Atomic bomb is an explosive weapon which derives potency from the conversion of the mass of radioisotopic nuclei to energy which is released in form of radiant heat [10].

An elaborate series of reactions are usually involved in the energy conversion process for atomic bombs. This is portrayed in the atomic bomb meaning that is given below;

The atomic bomb is a type of bomb that operates by releasing energy from spontaneous, self-sustaining and uncontrolled, nuclear chain reactions involving radioactive isotopes [1].

Lastly, the atomic bomb meaning is outlined based on its comparison to the hydrogen bomb;

Atomic bomb is a radioactive weapon that releases energy from nuclear fission or uranium and plutonium, thereby operating inversely with regards to the hydrogen bomb that releases energy from nuclear fusion of hydrogen isotopes [12].


Atomic Bomb Invention and History

The most widely recognized atomic bomb inventor is American physicist J. Robert Oppenheimer [6]. This is based on his contributions to the Manhattan research and development project between 1942 and 1946, authorized by President Franklin D. Roosevelt of the United States [13].

Earlier efforts which led to this invention include the discovery of nuclear fission reactions by Friz Strassman, Otto Hahn and Lise Meitner in 1938 [5].

A discovery by nuclear physicists in a laboratory in Berlin, Germany, in 1938 made the first atomic bomb possible, after Otto Hahn, Lise Meitner and Fritz Strassman discovered nuclear fission.

When an atom of radioactive material splits into lighter atoms, there’s a sudden, powerful release of energy. The discovery of nuclear fission opened up the possibility of nuclear technologies, including weapons.

Atomic bombs are weapons that get their energy from fission reactions. Thermonuclear weapons, or hydrogen bombs, rely on a combination of nuclear fission and nuclear fusion. Nuclear fusion is another type of reaction in which two lighter atoms combine to release energy.

The first atomic bomb test occurred on the 16th of July, 1945; in a project called the Trinity Test [3]. It was conducted in Los Alamos, New Mexico, on a remote site which had experienced desertification.

A plutonium explosive was used in this test and its explosion released a large magnitude of nuclear energy and a cloud of smoke up to 40,000 feet high.

Two atomic bombs have been dropped since the weapon was invented. These two bombs were called; “Little Boy” and “Fat Man” according to code names that were assigned to each one respectively.

‘Little Boy’ was the first atomic bomb which was dropped on Hiroshima in the Second World War. It was designed with a similar trigger mechanism as a gun, so that it could be detonated by propelling a radioactive mass through a cylinder to collide and react with another radioactive mass [2].

The bomb contained uranium, weighed approximately 9,700 pounds, and released explosive energy of about 15,000 tons of TNT when dropped from the B-29 Enola Gay aircraft.

Little Boy Atomic Bomb (Credit: Nick-D 2015 .CC BY-SA 4.0.)
Little Boy Atomic Bomb (Credit: Nick-D 2015 .CC BY-SA 4.0.)


‘Fat Man’ or ‘Mark III’ atomic bomb was implosive and had a rounded geometric design, and was composed of plutonium. It had a weight of about 10,300 pounds and released about 21,000 tons of TNT when dropped from the B-29 Bocksar aircraft on the city of Nagasaki.

Under the administration of President Harry S. Truman, the Little Boy and Fat Man atomic bombs were dropped by the United States Air Force on Japanese cities of Hiroshima and Nagasaki toward the end of World War II, between August 6 and August 6, 1945. These detonations caused the deaths of at least 200,000 people.

Fat Man Casing (Credit: Thomas Farley 2018 .CC0 1.0.)
Fat Man Atomic Bomb Casing (Credit: Thomas Farley 2018 .CC0 1.0.)


Thousands of nuclear weapon tests have been conducted since end of the Second World War. These tests have been carried out by various countries including Russia, the United States, China, North Korea, the United Kingdom, Pakistan, France, and India.

The development of the atomic bomb among other nuclear weapons has proceeded at a consistent pace. Treaties have been developed to control and limit the proliferation of such weapons.


Atomic Bomb Vs Hydrogen Bomb Comparison

A hydrogen bomb is more powerful than an atomic bomb, because the hydrogen bomb releases energy from nuclear fusion, which is a more energetic and spontaneous chain reaction than nuclear fission [9]. The magnitude of energy released from hydrogen bombs can be several times more than that which is released from atomic bombs as a result of this.

The main difference between the hydrogen bomb (also called H-bomb or thermonuclear bomb) and the atomic bomb is the reaction mechanism of energy release. Otherwise, they are both nuclear weapons and operate based on the chemical dynamics of radioactive elements.

We may consider the hydrogen bomb to be an advanced type of atomic bomb. It has a higher degree of complexity, and works based on a combined mechanism of nuclear fission and fusion reactions.

Early developments of the hydrogen bomb were further complicated by the need for equipment to keep isotopic liquid hydrogen under cryogenic (low temperature) conditions [11].


Comparison Criteria Atomic Bomb Hydrogen Bomb
Reaction Mechanism Fission Fission and Fusion
Radioactive Filling Plutonium, Uranium Plutonium, Uranium, Isotopic Hydrogen (Deuterium and Tritium, or D-T fuel)
Power 10^4 tons of TNT range 10^5 tons of TNT range
Design Weight Relatively Heavy Relatively Light
Relative Complexity Low High



Importance of Nuclear Weapons like the Atomic Bombs

The importance of nuclear weapons is linked to their role in technological development, international security, and diplomatic relations.

1). Role in Technological Development

Nuclear weapons such as the atomic bomb, have been influential in the development of nuclear energy technology.

These weapons have illustrated the energy potential of nuclear fuels like uranium, thereby playing a role in the development of innovative nuclear power plants and breeder reactors, which consume nuclear energy like a renewable form of energy, through fuel residue recycling. The advancement of nuclear energy in recent decades, and its adoption as a suitable source for electricity generation, have been hindered by public opinion about the safety and hazardous potential of this form of energy. This opinion has largely been created by nuclear weapons, or nukes as they are also called.

Lastly, the existence of nuclear weapons has influenced the decision-making process with regards to the development and use of various military, space and cyber technologies. This is due to the consideration that these technologies can increase the threat of nuclear weapons.


2). Role of Nuclear Weapons in International Security

Since the end of the Second World War, nuclear weapons have become a major factor in international security.

As a result of their highly-destructive potential, these weapons serve as a deterrent against potential military attacks [7]. They have also been a topic of deliberation with respect to how they can be managed with the least risk.


3). Role of Nuclear Weapons in Diplomatic Relations

As a deterrent to military attacks and a component of security and defense strategies, nuclear weapons have influenced diplomatic relations between various countries around the world.

These diplomatic influences have occurred in the form of treaties to regulate the use of nuclear weapons, research and development efforts, military agreements and joint operations, and weapons sharing, among others.



An atomic bomb is an explosive nuclear weapon that releases enormous amounts of energy when radioactive elements like plutonium and uranium undergo fission under uncontrolled conditions.

The history of this weapon dates back to the mid twentieth century when it was developed and used in the Second World War by the United States Air Force.

Atomic bombs are similar to hydrogen bombs in that both are nuclear weapons, however they differ based on their relative weight, power, and reaction mechanism. The main difference between atomic bombs and hydrogen bombs is that atomic bombs work by nuclear fission while hydrogen bombs work by nuclear fusion and release larger amounts of power and energy.

The importance of nuclear weapons includes;

  1. Role in Technological Development
  2. Role in International Security
  3. Role in Diplomatic Relations



1). Agam, M. A. (2018). “Nuclear Chain Reaction as a Model for PhD Research Exploration.” Journal of Advanced Research in Dynamical and Control Systems 09(special issue):1269-1277. Available at: (Accessed 27 July 2022).

2). Askew, J. (2017). “The science of Little Boy: Investigating the chemistry behind the first use of a nuclear weapon in warfare.” Science teacher (Normal, Ill.) 84(8):45-51. Available at: (Accessed 27 July 2022).

3). Beck, H. L.; Simon, S. L.; Bouville, A.; Romanyukha, A. (2020). “Accounting for Unfissioned Plutonium from the Trinity Atomic Bomb Test.” Health Physics Publish Ahead of Print(4). Available at: (Accessed 27 July 2022).

4). Hore-Lacy, I. (2007). “9. HISTORY OF NUCLEAR ENERGY.” Nuclear Energy in the 21st Century. Available at: (Accessed 27 July 2022).

5). Lander, G.; Steiner, M. (2015). “Revisiting the discovery of nuclear fission – 75 years later.” Journal of Neutron Research 18(1):3-12. Available at: (Accessed 27 July 2022).

6). Lewis, L. (2016). “Becoming Death, the Destroyer of Worlds: A brief psycho­biographical sketch of Dr. J. Robert Oppenheimer.” Available at: (Accessed 27 July 2022).

7). Mallick, (2021). “Limited War and Nuclear Deterrence.” Available at: (Accessed 27 July 2022).

8). Ochiai, E. (2014). “Devastation Caused by the Atomic Bombs: Hiroshima and Nagasaki.” Hiroshima to Fukushima (pp.35-37). Available at: (Accessed 27 July 2022).

9). Pappas, S. (2017). “Hydrogen Bomb vs. Atomic Bomb: What’s the Difference?” Available at: (Accessed 27 July 2022).

10). Pearson, E. F. (2013). “Hurricane Ike versus an Atomic Bomb.” Journal of Chemical Education 90(1):90-92. Available at: (Accessed.27 July 2022).

11). Petrescu, R. V.; Petrescu, F. I. T. (2020). “Contributions to the Hydrogen Fusion.” Available at: (Accessed 27 July 2022).

12). Shaltami, O. R. (2020). “Nuclear Bomb.” Available at: (Accessed 27 July 2022).

13). Welsh, T. S. (2017). “The Manhattan Project at Oak Ridge: Photographs of Ed Westcott, 1942-46.” Qualitative and Quantitative Methods in Libraries. Available at: (Accessed 27 July 2022).

14). Woolbright, S.; Michonova, E. (2014). “From the Dawn of Nuclear Physics to the First Atomic Bombs.” Available at: (Accessed 27 July 2022).

Similar Posts