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A question about Recoil force!

  1. Jun 22, 2010 #1
    when it is said that the recoil of a 120mm mortar is 40 tons, which one is meant to be the recoil: the reaction force exerted from gases on the recoil mass, OR the transmitted force from recoil system to the platform or vehicle (if it is mounted on a vehicle)?

  2. jcsd
  3. Jun 22, 2010 #2
    Both, depending on context. Also, a ton is not an SI unit of force.
  4. Jun 23, 2010 #3
    two words: conversion factors. :P
  5. Jun 23, 2010 #4
    two and a half words: variation of g.
  6. Jun 23, 2010 #5
    one word: negligible :)
  7. Jun 23, 2010 #6
    How about on an inclined plane at [itex]\alpha = 60^{\circ}[/itex]?
  8. Jun 23, 2010 #7
    Ok... I thought you were referring to g as gravity, and therefore variation in g would be negligible since this is not a super duper mortar. But now that you have mentioned an angle... I have no idea what you are talking about. Mind clarifying what you were referring to as "g"?

    Regardless, a ton is 2000 lbs and lbs easily convert to newtons which I assume are your desired "SI" units. Hence my, albeit somewhat snide, comment about conversion factors.
  9. Jun 23, 2010 #8
    What is a pound a unit of?
  10. Jun 24, 2010 #9

    Ranger Mike

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    recoil is 80,000 pounds force exerted on the mortar's base plate...
  11. Jun 24, 2010 #10
    pound is a unit of force as are tons as are newtons with newtons being the SI unit of force. I am done now, this is going nowhere.
  12. Jun 24, 2010 #11
    Why is the amount of groceries measured in units of force?
  13. Jun 24, 2010 #12

    1000Kg = 1 tonne. Is a unit of mass, not force. (1pound=0.45kg)

    http://en.wikipedia.org/wiki/Kilogram" [Broken]

    For force: 1Kgf = 1g N = 9.81 N (10N). g = gravitational acceleration (constant)

    http://en.wikipedia.org/wiki/Newton_(unit)" [Broken]

    From momentum conservation law.
    m1,V1-projectile mass and speed; m2,V2- mortar mass and speed
    And can calculate the force that generated the movement.
    40tf (40.000 Kgf) = 400KN (400,000 N)

    Last edited by a moderator: May 4, 2017
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