Author Topic: Brand new at this please help !  (Read 83993 times)

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Offline taper41

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Re: Brand new at this please help !
« Reply #90 on: May 30, 2012, 10:45:28 PM »
Come on now -- why do you all try to answer these hypothetical questions for someone who isn't, nor probably will never, build something.  It's an exercise in jacking-off, and you're all at hand.

(So to speak.)

Stan,
Sometimes this stuff just plain gets interesting.

And.... you never know about someone like taper41..... he may have been helped in ways that none of us fully understand (perhaps not even he)..... If he comes out of engineering college with a degree in this stuff, there is a huge chance that he takes a career opportunity in the field of aerodynamics....it will pay him good... and, if he remembers this, that a lot of real world hotrodders who don't and never will have the "book learning" ar actively engaged in "seat of the pants" modification to vehicle aerodynamics, there is a chance albeit smaller that if or when he has spare time, he may get involved in some design of bodies for use in land speed racing. (I can hope and dream, can't I)


i would help because thats the kind of person i am

Offline manta22

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Re: Brand new at this please help !
« Reply #91 on: May 30, 2012, 11:07:09 PM »
Mike (taper41);

Frankly, I think you are just wasting everyone's time with your interminable questions. You ask a question and someone answers that question so you change that question into another one. Are you enjoying leading everyone around in circles?
If, as you said, you are studing Physics, it sounds as if you haven't read more than a page or two of a Physics 101 textbook. There is a fellow named Franklin Ratliff that would probably be willing to help you-- look him up on Google and get in contact.
Regards, Neil  Tucson, AZ

Offline Stan Back

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Re: Brand new at this please help !
« Reply #92 on: May 30, 2012, 11:08:47 PM »
And a round of English could help you communicate more better two.
Past (Only) Member of the San Berdoo Roadsters -- "California's Most-Exclusive Roadster Club" -- 19 Years of Bonneville and/or El Mirage Street Roadster Records

Offline taper41

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Re: Brand new at this please help !
« Reply #93 on: May 31, 2012, 09:48:46 AM »
aerodynamic drag forces increase by the square of the rate of speed change


drag horsepower increases by the cube of the speed change


larry so how is a 25% change in either going to end in the same result ?

McRat

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Re: Brand new at this please help !
« Reply #94 on: May 31, 2012, 10:09:25 AM »
Isn't that backwards?

I thought aero went up as a cubic function.  Traction is linear.  Twice as much HP needs twice as much traction.  Twice as much speed requires 8 times the HP?

Dunno.  Push pedal on right hard, point towards finish, pull to right when it explodes ...

Offline rgn

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Re: Brand new at this please help !
« Reply #95 on: May 31, 2012, 10:13:32 AM »
So is this where you show your hand and become the belittler, or have you been on Wikipedia?   What actually is the purpose of your post Taper?

Offline taper41

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Re: Brand new at this please help !
« Reply #96 on: May 31, 2012, 10:37:10 AM »
mcrat here read this article maybe im misunderstanding .....

In truth, aerodynamic forces increase in an exponential manner. In this particular case, the aerodynamic drag forces increase by the square of the rate of speed change. An increase in speed of 6 times, from 10 mph to 60 mph, would increase the force by 36 (6 squared, or 6x6) resulting in an increase of the force on your hand from 2 lbs. to 72 lbs. (36 x 2 lbs.). This is the main reason why cars run into an "Aero Wall" with increasing speed.

 

Drag horsepower - Another important fact is that the horsepower required to increase the speed of the car (and overcome drag) is also increasing at an exponential rate. In this case, drag horsepower increases by the cube of the speed change. Using the same example, your hand carries 2 lbs. of drag force at 10 mph. This equates to just .053 drag hp, certainly not a lot of drag horsepower! Let’s increase the speed by 6 times to 60 mph and see what happens. We already know that the drag force increases from 2 lbs. to 72 lbs. Using the cube of the speed change (6x6x6), times the original drag horsepower (.053), the drag horsepower increases to 11.5 hp (.053 x 6x6x6 = 11.5). This is the clearest example of why aerodynamic drag is so amazingly critical to racecar performance.

Offline Seldom Seen Slim

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Re: Brand new at this please help !
« Reply #97 on: May 31, 2012, 11:32:20 AM »
Unh, ladies and gentlemen -- where's this thread of discussion going?  Taper labelled it saying that he's brand new and needs help -- and now he's giving lessons in what he feels he knows.  While that's fine, I guess -- it sure doesn't relate to offering help to him.

Please -- either get back to asking for help - and then either accepting what's offered or, if you feel the need to dispute or get specifically technical -- do it in private.  This site is for help and education - but not lecturing, please.

Thanks.
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Offline taper41

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Re: Brand new at this please help !
« Reply #98 on: May 31, 2012, 11:47:41 AM »
i am asking for help, my question was is power and aerodynamics interchangeable when it comes to getting the same result, and received an answer but do not quite understand it thats all, im confused from the article i read and what the answer was .

the question i had was if you decrease the aerodynamic drag by 25% or add power by 25% would the result differ or be the same, if it was on the same vehicle

Offline jl222

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Re: Brand new at this please help !
« Reply #99 on: May 31, 2012, 12:18:59 PM »
i am asking for help, my question was is power and aerodynamics interchangeable when it comes to getting the same result, and received an answer but do not quite understand it thats all, im confused from the article i read and what the answer was .

the question i had was if you decrease the aerodynamic drag by 25% or add power by 25% would the result differ or be the same, if it was on the same vehicle

  Taper41.. it's getting real hard to believe your a physics student, because you don't even get the hint of not capitalizing

  The I NOT i and were you being disrespectfull by not capitalizing McRat?

   I wish I had such an easy question in physics 53yrs ago, I would have gotten a better grade. Today with the internet, answers would be easy.

      JL222

Offline taper41

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Re: Brand new at this please help !
« Reply #100 on: May 31, 2012, 12:30:08 PM »
t Jl I didn't say I was a student for a long period of time did I? Instead of mocking me, if the answer is so easy than i would appreciate it if not then that's fine.

Offline Seldom Seen Slim

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Re: Brand new at this please help !
« Reply #101 on: May 31, 2012, 12:44:17 PM »
Taper41:  My point is that we're here to talk about land speed racing, and not to have you and someone trading barbs - including use of the word "mocking".  That stuff is for private messages or emails.  Those addresses are listed, if the sender wants them posted, with each post.  Take it off the open Forum if you've got axes to grind, hey?  Thanks.

If you haven't already looked, do investigate the concept of being asked to not post again on any forum.  it might help sharpen your focus on what you really want to do.
Jon E. Wennerberg
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 (that's way up north)
2 Club member x2
Owner of landracing.com

Offline jl222

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Re: Brand new at this please help !
« Reply #102 on: May 31, 2012, 12:52:00 PM »
t Jl I didn't say I was a student for a long period of time did I? Instead of mocking me, if the answer is so easy than i would appreciate it if not then that's fine.

  Still...The small i :roll:

Offline Glen

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Re: Brand new at this please help !
« Reply #103 on: May 31, 2012, 12:53:48 PM »
now it's English and spelling lessons
Glen
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South West, Utah

Offline jl222

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Re: Brand new at this please help !
« Reply #104 on: May 31, 2012, 01:10:18 PM »
now it's English and spelling lessons

  Glen... Just making the point about how hard it is to get the point across.
   
       JL222