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Homework Help: Work, bullet velocity, question. Please help

  1. Feb 16, 2010 #1
    If the gun is fired in a horizontal direction, 1.5 m from the ground, what is the theoretical limit for the horizontal displacement that the bullet can reach before it falls to the ground? Note: To obtain the maximum amount of work, assume that the gas expansion is quasi-static and isothermal.

    This is what I did but not sure if it is right:

    V1 = 0.3 cm2 * 15 cm = 4.5 cm3
    V2 = 0.3 cm2 * 90 cm = 27 cm3

    I did W = -RTln(V2/V1) = 4439 J

    Im not sure if that is right because i dont know if it should be looking at the pressure change and the volume change? Is another formula required because where does the constant volume come into play because they gave me that. And finally, I don't know how to tranform the work into kinetic energy and thus find the distance. I know the formula, but not sure what to do.

    http://img34.imageshack.us/img34/179/81192194.jpg [Broken]
    Last edited by a moderator: May 4, 2017
  2. jcsd
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