Soft Object Hitting a Fast Moving Target

Discussion in 'General Science & Technology' started by mustangbaby, Jul 30, 2009.

Thread Status:
Not open for further replies.
  1. mustangbaby Registered Member

    Messages:
    1
    I have a question. This just happened to me:

    I was riding on a rollercoaster (65 mph), when all of a sudden I felt what seemed like a rock hitting the side of my head just above my right temple. It hurt like hell and I thought I would pass out. I thought for sure it was a rock, but a person 2 rows behind me said 'no, it's ice cream' - he had it all over him and so did my son who was sitting behind me. The point where it hit my head swelled a little and I was left with a throbbing, stinging pain (and, yes, there were remnants of ice cream in my hair and on my head). I also had a cut (like a scrape) where it hit me. The part of the rollercoaster where this happened goes close to the ground and I suppose someone walking by (some idiot!) could have thrown an ice cream cone or cup of ice cream at the coaster.

    My question is - would something soft like ice cream hit me (I was going 65 mph) hard enough and cause that much pain and actually cut my skin! It seems impossible, but I admit, I don't know much about physics, etc.

    :shrug:
     
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. GeoffP Caput gerat lupinum Valued Senior Member

    Messages:
    22,087
    Hmm...maybe it was well frozen? Though at that speed a bug hitting you would sting, so presumably anything seeming even insignificant would hurt.
     
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. BenTheMan Dr. of Physics, Prof. of Love Valued Senior Member

    Messages:
    8,967
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Enmos Valued Senior Member

    Messages:
    43,184
    Uh.. I had a collision with a large bumblebee once while riding a bike pretty fast. It hit me in the face. Believe me, the impact feels like someone hits you with a hammer.
     
  8. Enmos Valued Senior Member

    Messages:
    43,184
    Perhaps the cone or cup hit you first. Perhaps there was one of those plastic mini spoons in it as well which might account for the scrape ?
     
  9. Dywyddyr Penguinaciously duckalicious. Valued Senior Member

    Messages:
    19,252
    Ever been hit in the face by a simple raindrop at 100 MPH?
    It hurts...
     
  10. cosmictraveler Be kind to yourself always. Valued Senior Member

    Messages:
    33,264
    Anything that is traveling at a high rate of speed can hurt you if it hits you where you are unprotected. As was stated even a simple raindrop can cause allot of pain when it hits you at high speed. I know, I drive a motorcycle and can assure you it does sting!
     
  11. Dywyddyr Penguinaciously duckalicious. Valued Senior Member

    Messages:
    19,252
    Pfft, real bikers ride the bike, they don't drive it.

    Please Register or Log in to view the hidden image!

     
  12. cosmictraveler Be kind to yourself always. Valued Senior Member

    Messages:
    33,264
    When you get my age, you drive!

    Please Register or Log in to view the hidden image!

     
  13. Fraggle Rocker Staff Member

    Messages:
    24,690
    It's all about inertia. Look at the automobile crash tests.

    If two cars of equal mass traveling at the same speed in opposite directions collide head-on, they will both come to a complete stop and each will absorb half the impact, with the concomitant crumpling of the metal and trauma to the passengers. But if one has twice the mass of the other, it will push the other car backward, thereby decelerating at a slower rate, and absorbing less of the impact, suffering less of the damage, and causing less trauma to the humans; while the other car and its passengers declerates faster, absorbing more of the impact and suffering greater damage and injury. This is why Americans drive Hummers (instead of learning to drive better or putting breathalyzer ignition interlocks in every car).

    So if you are hit by one drop of cream, you have more inertia so it will come to an abrupt stop and start moving backward, causing very little trauma to your face.

    But what if you run into a 150lb scoop of cream--frozen or not? The molecules behind the ones that come into direct contact with your face have inertia, and there's a limit to how quickly they can decelerate to get out of the way of the ones that are now moving backwards. If the cream is frozen solid, you and the cream will suffer roughly the same degree of trauma. If it's liquid, then you'll come out a little bit ahead in the fight, but still a head-on collision with 150lb of liquid at, say, 50mph, will be extremely painful, like a belly-flop dive.

    If you hit an errant ice cream cone--something midway between a drop of cream and a man-sized block of it, then it took most of the blunt force trauma, but as you now know, it was big enough to fight back and cause you a little bit of pain.
     
  14. GeoffP Caput gerat lupinum Valued Senior Member

    Messages:
    22,087
    Well how do you know unless you hit yourself with a hammer to compare?
     
  15. Enmos Valued Senior Member

    Messages:
    43,184
    It's a figure of speech

    Please Register or Log in to view the hidden image!



    I did leave something out though. It hit me right in the eye..
     
Thread Status:
Not open for further replies.

Share This Page