sound barrier

Discussion in 'Politics & Religion' started by Gordon Gekko, Oct 15, 2002.

  1. well, i don't know much about guns. with this sniper stuff all over the news (unbelievable), i had been wondering if the victims were able to hear the gunshot before they were hit. so basically, i wanted to find out if bullets can travel faster than sound. anyway, in my quest to find this information, i found some really cool stuff (i think). the following are a real image and video of a plane breaking the sound barrier. i think it looks awesome. i've never seen anything like this before.

    http://www.kettering.edu/~drussell/Demos/doppler/mach1.jpg

    http://www.kettering.edu/~drussell/Demos/doppler/mach1.mpg (well worth the short download, very cool)

    http://www.gmi.edu/~drussell/Demos/doppler/doppler.html
     
  2. Have you ever seen or heard it live??

    It is awesome to see the plane fly by and then hear the crackling thunder rolling behind it 2 or 3 seconds later... I dont think this is allowed anymore at air shows......
     
  3. Great stuff!

    Thanks Gordon
     
  4. Gordon,

    Some rifles have a muzzle velocity of 3,000 meters per second, which is well above the sound barrier.

    My guess is that you wouldn't hear a thing, unless you were shot in the chest and lived for awhile.

    Unfortunately, this is somewhat close to where I live and it is disturbing. The thought of packing up the car with my wife and having her drop dead right next to me would screw me up for life.

    Halloween in this entire area is going to be cancelled IMO if they don't find this guy or woman before then. I'm assuming it is a guy, but you can't be sure.

    This person is just a sick, senseless killer. We're not dealing with a human being but a broken machine that has snapped.
     
  5. I just hope the cops shoot him before he can be captured and tried.

    Getting your head blown off is probably a more effective deterrent for idiots like that sniper...
     
  6. I think you mean FPS not MPS.
     
  7. for the record, i'm not a believer in predetermined fate. anyway...

    can you imagine if the latest sniper victim knew how she would die? imagine if you were her and someone said, "you'll die at age 47, in a home depot parking garage, right next to your husband. you'll be shot in the head by a serial killer that randomly snipes people."

    she never even knew what happened. can you imagine walking to your car and you're alive one instant and dead the next? you're just suddenly dead; no warning at all.

    how about the guy that got killed getting gas for his car. imagine if as he pulled into the gas station, someone were to tell him, "you're about to die in a few seconds." he'd be like, "WHAT?!"
     
  8. OHLC

    OHLC

    A 223 with a 68 grains bullet can be pushed to about 2800fps.
    The 55 grainer reaches 3100-3200fps from a standard barrel.
    So, the bullet is supersonic.

    Three cases regarding the sound :

    Supersonic round, no silencer :
    The sound is heard near the shooter, and through all the trajectory, as long as the bullet is supersonic.

    Supersonic, silenced :
    Sound heard through the whole trajectory.
    The silencer is just there to make it less easy to spot the shooter.

    Subsonic, silencec :
    Sound unheard of, neither on the initial release, nor during the trajectory.

    OHLC
     
  9. Oops, you're right. That would make a big difference.
     
  10. for those that don't know, sound travels at ~1126 feet per second.
     
    #10     Oct 15, 2002