HomeLatest ThreadsGreatest ThreadsForums & GroupsMy SubscriptionsMy Posts
DU Home » Latest Threads » Forums & Groups » Topics » Environment & Energy » Environment & Energy (Group) » UCLA researchers create h... » Reply #29

Reply #29


Response to Spitfire of ATJ (Reply #18)

Sun Aug 5, 2012, 05:47 PM

29. MYTH - "Old Wives Tale"

It's purely a MYTH that physicists and engineers said that the sound barrier couldn't be broken.

It has been know for a LONG, LONG time that the crack of a whip is due to the tip going super-sonic. So there can't be any physical laws that are violated by going faster than sound.

There were engineering concerns about whether one could get jet / rocket engines that could produce enough power to compensate for the immense drag caused when one goes super-sonic. The shock-wave that is the "bow wave" of a supersonic aircraft saps lots of energy. Until recently, the only way to go supersonic was to use after-burners on the jet engines. That limited super-sonic flight to a few tens of minutes.

The new F-22 stealth fighter is the first craft that has "super-cruise" and can go super-sonic without the use of after-burners on the engines.

I don't care how efficient it is. It is merely a scheme to "borrow from Peter to pay Paul". Any energy that is converted into electricity comes out of that which could otherwise be used for lighting. You can't "double count" the energy and use a given incident photon for both lighting and electricity; regardless of how efficient you get.

You do understand that, don't you?

PamW

Reply to this post

Back to OP Alert abuse Link to post in-thread

Always highlight: 10 newest replies | Replies posted after I mark a forum
Replies to this discussion thread
Arrow 32 replies Author Time Post
OKIsItJustMe Jul 2012 OP
silverweb Jul 2012 #1
jillan Jul 2012 #2
drm604 Jul 2012 #3
AtheistCrusader Jul 2012 #7
drm604 Jul 2012 #12
AtheistCrusader Jul 2012 #13
drm604 Jul 2012 #21
limpyhobbler Jul 2012 #4
rhett o rick Jul 2012 #5
PamW Jul 2012 #6
AtheistCrusader Jul 2012 #8
PamW Jul 2012 #15
AtheistCrusader Jul 2012 #17
Spitfire of ATJ Jul 2012 #9
PamW Jul 2012 #14
Spitfire of ATJ Jul 2012 #18
Nederland Jul 2012 #20
LineLineLineLineLineNew Reply MYTH - "Old Wives Tale"
PamW Aug 2012 #29
Spitfire of ATJ Aug 2012 #30
PamW Aug 2012 #31
Spitfire of ATJ Aug 2012 #32
PamW Jul 2012 #16
Spitfire of ATJ Jul 2012 #19
AtheistCrusader Jul 2012 #22
OKIsItJustMe Jul 2012 #23
PamW Jul 2012 #24
XemaSab Jul 2012 #25
Exen Trik Jul 2012 #10
PamW Jul 2012 #27
OKIsItJustMe Jul 2012 #11
PamW Jul 2012 #26
OKIsItJustMe Aug 2012 #28
Please login to view edit histories.