Nuclear Bomb Explosions: Speed & Energy Release

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Discussion Overview

The discussion revolves around the speed of nuclear fusion and fission reactions during a nuclear explosion, the timing of energy release, and the relationship between energy concentration and explosion speed. Participants explore theoretical aspects of nuclear reactions and their implications in both bombs and reactors.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether nuclear fusion/fission reactions occur at the speed of light and seeks clarification on the timing of energy release relative to the explosion.
  • Another participant asserts that nuclear fission does not occur at the speed of light and describes the prompt neutron lifetime and rapid neutron multiplication during a nuclear explosion.
  • There is mention of the yield of a nuclear explosion being dependent on the number of fissions that occur before the fissile mass dissipates.
  • It is noted that thermonuclear explosions are initiated by fission-based triggers, leading to a fission detonation before the thermonuclear detonation.
  • A participant expresses uncertainty about energy release timing, suggesting that energy should not be released until after the explosion.
  • Another participant discusses the importance of proper construction of nuclear warheads to ensure sufficient fission reactions occur before the mass dissipates.
  • There is a comparison made between nuclear bombs and reactors, highlighting the controlled nature of reactions in reactors versus the uncontrolled reactions in bombs.

Areas of Agreement / Disagreement

Participants express differing views on the timing of energy release in relation to the explosion, with some suggesting energy is released only after the explosion while others provide information that implies energy is released during the reaction process. The discussion remains unresolved regarding the precise timing and mechanics of energy release.

Contextual Notes

Participants reference varying sources of information regarding the speed of reactions and energy release, indicating potential discrepancies in definitions and understanding of nuclear processes. There are also assumptions about the construction and functioning of nuclear devices that are not fully explored.

Bison01
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hey guys just a simple question, I think.

How fast does the nuclear fusion/fission reactions n explosion occur? Is it at the speed of light?

Will there be any energy release b4 the explosion, Or should only b after the explosion? I always thought the fission/fusion reaction cause it to explode then release energy.

Does the high concentration of energy in Nuclear bombs have something to do with the speed of its explosion? Does it mean the more concentrated the energy the faster it will explode logically?

Thnx in advance.
 
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Nuclear fission does not occur at the speed of light.

Nuclear explosions are an example of a prompt supercritical process that is rather unique. The prompt neutron lifetime is on the order 10-7 s, or 0.1 us.

There is a neutron source to get started, but once started the neutron multiplication occurs very rapidly - on the order of microseconds.

The yield is determined by how many fissions can occur before the fissile mass dissipates.

Thermo nuclear explosions are initiated by fission-based triggers, so there is a fission detonation before the thermonuclear detonation.
 
Thnx for the response

Its just that I read some site where it says the reactions occur n explode at hundred billionth of a second, I jus wanted to confirm it.

So I am guessing no energy should be released til after the explosion.

thnx for the additional info. good night. Peace.
 
Bison01 said:
Thnx for the response

Its just that I read some site where it says the reactions occur n explode at hundred billionth of a second, I jus wanted to confirm it.

So I am guessing no energy should be released til after the explosion.

thnx for the additional info. good night. Peace.

Each time a reaction happens it releases the same amount of energy. If you don't build it correctly, the warhead will get blown too far apart for any more fission to occur before you can reach a large explosion.

For example, in nuclear reactors they use radioactive materials to generate heat to power a steam turbine. The materials are carefully protected by control rods that absorb neutrons and keep them from initiating too many reactions at once and leading to a runaway reaction. Same effect as a nuclear bomb, but it's a controlled reaction instead.
 

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