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Questions about explosive

  1. Feb 11, 2006 #1
    I read that gun use hight pressure gas to push the the projectile
    And the speed of explosion is limit at ~ 3km/s
    And I read that in a shaped charge explosion, the jet can travel faster than 7km/s easily

    Can anyone tell me what is the different betwen these two explosion?
    What the speed of explosion depend on?
    Why in a shaped charge they only use normal chemical but the speed is too hight than normal?
    Why dont they use shaped charge as propellant for gun?
    Is the velocity of detonation mean the speed of blast waves of explosion?

    My speciality is not much relate to physics but Id like to know, I tried google alot but it isnt effected, so please help me

    Anyway, thank for reading
  2. jcsd
  3. Feb 11, 2006 #2


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    The chemical charge used to propel a shell in artillery or bullet in a gun is a low explosive with a relatively low detonation velocity. In contrast, a shaped charge often uses a high explosive with a high detonation velocity.

    If one where to use a high explosive to propel a shell, then the gun would likely explode, which would be counterproductive to the purpose of the gun.
  4. Feb 11, 2006 #3


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    The deflagration rates of ballistic propellants are measured in m/s, and the reaction front is propagated by thermal excitation; the detonation rates of explosives are measured in km/s, and the reaction front is propagated by the shock wave associated with the detonation.
  5. Feb 11, 2006 #4


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    In general, propellant charges have the oxidant and fuel as separate components which are mixed. The high explosive have the oxidant (ONO2 group) as part of the molecule, e.g. TNT, RDX or HMX.
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