4 ms·
> "Mr. Eustace cut himself loose from the balloon with the aid of a small explosive device and plummeted toward the earth at a speeds that peaked at more than 8
by Crito 12y ago
> "Mr. Eustace cut himself loose from the balloon with the aid of a small explosive device and plummeted toward the earth at a speeds that peaked at more than 800 miles per hour, setting off a small sonic boom heard by observers on the ground."
I was under the impression that the "faster than the speed of sound" thing was technically deceptive, since it used the speed of sound at sea-level but they were only doing that many miles up where the speed of sound was much higher. Terminal velocity should always be lower than the speed of sound, is my thinking here. If that is the case, then I wouldn't expect a sonic boom.
Is it actually the case that they have enough momentum to continue to fall that fast as they enter the denser atmosphere?
- matthewmcg 12y agoThe speed of sound actually decreases, and then increases again as you go up in altitude. So when they say faster than the speed of sound, they mean the local speed of sound (hence the sonic boom). This is explored (with graphs!) here for the case of Mr. Baumgartner's jump: http://blog.wolfram.com/2012/10/24/falling-faster-than-the-speed-of-sound/ http://blog.wolfram.com/2012/10/24/falling-faster-than-the-s...
- seanflyon 12y agoI think he built up speed in the high atmosphere were the air is thin and was still going fast when he reached denser air and thus was going faster than the speed of sound in the denser air.