Question about Boston Image

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Just a question about the scene I was wondering if anyone knew if it was possible for the glass to be so far out in the sidewalk when supposedly the bomb went off on the sidewalk?

Someone posted something about the physics in an earlier thread. Essentially the air pressure can create a vacuum (if I remember correctly) pulling the windows out of place.

Another thing to consider is that some glass is shatter resistant, yet under enough stress will give, if something like that is pushed hard from one side as it rebounds it can shatter in the opposite direction of the force being applied. This is something I was curious when I saw double paned glass and in one case, only the outer pane was shattered.

Also, this would "shatter" the idea that the glass was somehow broken from the inside out.





In any case, the reverberating glass that I suggested does not seem like the likely culprit although I do wonder if this is possible. In the case of bomb blast, it would probably leave the glass on the inside of the building and not what we saw in Boston.

I have found a good article on explosion physics to help you understand:

Blast wind: At the explosion site, a vacuum is created by the rapid outward movement of the blast. This vacuum will almost immediately refill itself with the surrounding atmosphere. This creates a very strong pull on any nearby person or structural surface after the initial push effect of the blast has been delivered. As this void is refilled, it creates a high-intensity wind that causes fragmented objects, glass and debris to be drawn back in toward the source of the explosion.

www.howstuffworks.com...

I might be going overboard on calling the article "good" as there are probably better resources out there, but none-the-less, hope this helped.

reply to post by boncho


Further more, most stores use special glass which fragments down into tiny crystals rather than shards of the pane, so there is less chance of injury, similar to wind-shield glass.
Thanks for your explanation though, I'm not very verbose when trying to explain technical things sometimes haha

Thank you guys, that does make sense that if the explosion forced the atmosphere in primarily a single direction that it would create a vacuum. I saw the one picture and at first glance it did not make sense to me and berfore I make any statement on what I truly believe happened I would like to have all evidence that I can find checked and verified.

Click here for more information.

Originally posted by pacifier2012
edited out by me in light of your removed post...

You don't have to have to personify and attack a poster who noticed a strange picture and asked a question. Don't ever back down from asking questions that's how you learn. Thought police, and all that..

The photo makes sense to me, but at first I was like huh? The glass would have moved much further if the bomb was inside.. The spread is pretty minimal so I agree with some of the above analysis..

Calling people "not real people" by insinuation is very ignorant.

Here is what you responded too:

Just a question about the scene I was wondering if anyone knew if it was possible for the glass to be so far out in the sidewalk when supposedly the bomb went off on the sidewalk?

Just think about it..