Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Physics (https://www.askmehelpdesk.com/forumdisplay.php?f=258)
-   -   Ask physics questions ? (https://www.askmehelpdesk.com/showthread.php?t=577775)

  • May 23, 2011, 07:40 AM
    namwireman
    Ask physics questions ?
    An anti-shipping missile Exocet type weight 1,500 lbs, with a 360 lbs. warhead traveling at 1,030ft/s. Hits a WW2 type US battleship on a turret with 17" of armor. How far will the missile penetrate?
  • May 23, 2011, 07:43 AM
    Curlyben
    Who cares as the explosives WILL kill you anyway.

    Look at the General Belgrano in the 80's..
  • May 23, 2011, 10:28 AM
    Unknown008

    Actually... I think I would be satisfied knowing how to work this out ;)

    And on the other side... wrong link Ben! :eek: You put an 'i' which shouldn't be there.

    ARA General Belgrano - Wikipedia, the free encyclopedia
  • May 23, 2011, 10:44 AM
    Curlyben
    Right link, wrong spelling.

    Now I must admit when I did Physics I was taught in SI units, so Imperial gets me stumped ;)
  • May 23, 2011, 10:49 AM
    Unknown008

    Ah, me too :)

    I'll use my conversion script ;)

    Quote:

    An anti-shipping missile Exocet type weight 680.39 kg, with a 163.29 kg. warhead traveling at 396.24 m/s. Hits a WW2 type US battleship on a turret with 0.43 m of armor. How far will the missile penetrate?
  • May 23, 2011, 10:54 AM
    Curlyben
    Of course I forgot the really important fact here that negates my previous comment.

    The Exocet is a French made missile, so is likely to fail or surrender, before it explodes..

    Anyway this is a momentum problem.
    I can't remember the equations mind.
    Mass is 1076.68 Kg
    Speed is 396.24 m/s

    So I'm guess force = mass x speed

    And from there, well...
  • May 23, 2011, 11:01 AM
    Unknown008

    Hm... if that's merely momentum... then it should be more or less okay I guess...

    wrong mass =S

    Mass = 843.68 kg
    Speed = 396.24 m/s

    Momentum = 334299.76 N/s

    Then... we don't have the mass of the battleship, nor the 'recoil' (I know it might not be the correct term :o) of the battleship when it is hit by the missile... otherwise, I'd apply the principle of conservation of momentum.
  • May 23, 2011, 01:15 PM
    jcaron2

    Namwireman, have you been given a formula for penetration depth as a function of kinetic energy or other properties?

    Otherwise it seems we need to resort to the French DeMarre Armor Penetration Formula of 1890. In that case, I believe the correct form of the formula for homogeneous steel armor would be

    ,

    where k and p are constants relating to projectile nose shape, projectile size, projectile damage, definition of "penetration," plate type, and obliquity of the angle of impact.

  • All times are GMT -7. The time now is 06:54 AM.