Barrel roll
in [Aussie Drivers]
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From: D Walford on 18 Jun 2010 04:23 On 17/06/2010 9:44 PM, George W Frost wrote: > "D Walford"<dwalford(a)internode.on.net> wrote in message > news:4c19d113$0$28643$c3e8da3(a)news.astraweb.com... >> On 17/06/2010 2:06 PM, Mark Walford wrote: >>> On 17/06/2010 1:43 PM, atec7 7> wrote: >>>> Mark Walford wrote: >>>>> On 16/06/2010 12:41 PM, Doug Jewell wrote: >>>>>> George W Frost wrote: >>>>>>> "Diesel Damo"<Diesel_4WD(a)yahoo.com.au> wrote in message >>>>> What about the potential energy stored in the cars suspension as it >>>>> begins the monuever? Compressed by the ramp and then released as the >>>>> car turns over. Shouldnt the suspension push the car away from the >>>>> roof regardless of its speed? >>>>> >>>>> Mark >>>> Of course it does but the figures supplied more than compensate when you >>>> realise the minimum speed is quite slow in relation to the estimated in >>>> the clip hence a safety margin and a bit >>> Fair enough. >>> >>> You've seen this? >>> >>> http://www.youtube.com/watch?v=-TbpgZ2Dt0A&feature=player_embedded >>> >> Now I know what you do at work all day:-) >> >> >> >> Daryl > > > So is Mark your little boy Yes but not so little any more, almost 24 and over 6' tall and he drives a supercharged Toyota AE86 Sprinter:-) > and this is where the profits are going?> > He works for an IT company so not my profits:-) Daryl
From: Doug Jewell on 18 Jun 2010 04:27 Mark Walford wrote: > On 16/06/2010 12:41 PM, Doug Jewell wrote: >> George W Frost wrote: >>> "Diesel Damo" <Diesel_4WD(a)yahoo.com.au> wrote in message >>> news:9394786d-5657-4b41-a1cb-b3c7ad5c9104(a)23g2000pre.googlegroups.com... >>> On Jun 15, 10:57 pm, "George W Frost" <georgewfr...(a)gmail.com> wrote: >>>> "Clocky" <notg...(a)happen.com> wrote in message >>>> >>>> news:4c1770ac$0$28671$c3e8da3(a)news.astraweb.com... >>>> >>>>> George W Frost wrote: >>>>>> This youtube video depicts a Mercedes 2011 Gull wing roadster doing a >>>>>> barrel roll through a tunnel in Fraser Canyon British Columbia Canada >>>>>> http://www.youtube.com/watch?v=ihaSDlGOTn4 >>>>> Pity it's not real. >>>> Just because you can't drive, doesn't mean that it is a fake >>> >>> Hahaha. Oh man, I was going to reply to Clocky saying that I didn't >>> think that needed to be pointed out, but here's you eating it up with >>> a big spoon. Jesus you're thick LOL. >>> >>> >>> ************************** >>> >>> There has been checks on this via the web and snopes and any other >>> sources and there has to date, been nothing to indicate that it is a >>> hoax. >>> Bringing to mind, a toy >>> >>> Yes, a toy, a toy car racing set, which has loop the loop and barrel >>> rolls in the track, >>> these toys do not fall out of the sky when performing the tricks >>> So, why can't a bigger car do the same ? >>> A 6 cylinder 130 HP airplane can do barrel rolls at 200kph, >>> so why not a V12 600 HP powered car ? >> >> Using a bit of maths... >> Centripetal force = mV^2/r >> gravitational force = mG >> these two must cancel out >> so mG = mV^2/r >> solving for V >> V= SQRT(G x r) >> which will give the minimum ANGULAR velocity that the vehicle must >> travel around the curve in. >> at a very rough guess I'd say the radius of the curve to be 4m which >> means >> V=SQRT(9.8 x 4) = 6.26 m/s >> >> a circle of 4m radius has a circumference of 25.12m >> which at 6.26m/s would take 4sec to complete. Therefore if the car does >> the loop in less than 4 sec, it won't fall. >> >> Now, that is for a perfectly round tunnel, which this isn't - because >> this is elliptical the effective radius at the top is larger, requiring >> a higher angular velocity. >> >> But I would have to say though, that what the video shows is certainly >> possible. >>> >>> >> >> > What about the potential energy stored in the cars suspension as it > begins the monuever? Compressed by the ramp and then released as the car > turns over. Shouldnt the suspension push the car away from the roof > regardless of its speed? Well it would push it away a little, but not much. If we assume the car is travelling at the minimum necessary angular velocity, so the Centripetal Force is exactly equal to the gravitational force: (In practice you would go somewhat faster than minimum to ensure that the vehicle stayed on the roof). As the car starts the curve it will have a net force of approx 2G acting on it, which will compress the suspension. As the car turns, the force will slowly decrease, and the suspension will extend. Ultimately, by the time the car is inverted, CF & GF cancel out, and so the car has 0 effective weight. But the suspension will be fully extended, so it can no longer apply any force of it's own. Thus the suspension doesn't enter into the equation. If the suspension was on a ratchet, so once it compressed you held it there until the top of the curve, then released it, then yes it would push it away, but it doesn't work like that. Because it compresses & releases continuously depending on the net force, it won't push the vehicle off the roof. > > Mark -- What is the difference between a duck?
From: Evan on 18 Jun 2010 07:28 > > George W Frost wrote: > >> This youtube video depicts a Mercedes 2011 Gull wing roadster doing a > >> barrel roll through a tunnel in Fraser Canyon British Columbia Canada > > >> http://www.youtube.com/watch?v=ihaSDlGOTn4 "George W Frost" <georgewfrost(a)gmail.com> wrote: > There has been checks on this via the web and snopes and any other sources > and there has to date, been nothing to indicate that it is a hoax. > Bringing to mind, a toy > > Yes, a toy, a toy car racing set, which has loop the loop and barrel > rolls in the track, > these toys do not fall out of the sky when performing the tricks > So, why can't a bigger car do the same ? > A 6 cylinder 130 HP airplane can do barrel rolls at 200kph, > so why not a V12 600 HP powered car ? Did I mention that everyone should report this to Mythbusters?
From: hippo on 19 Jun 2010 03:48 Noddy wrote: > > > "GrassyNoel" <geracen(a)iinet.net.au> wrote in message > news:7a7e2ac7-d44c-4084-a679-7b2998ef584e(a)j36g2000prj.googlegroups.com... > On Jun 15, 2:00 pm, "George W Frost" <georgewfr...(a)gmail.com> wrote: > > > http://www.youtube.com/watch?v=ihaSDlGOTn4 > > The first assumption is, of course, that they faked it with animation, > i.e. CGI. > > It was as fake as one of Kevin Rudd's promises. > > -- > Regards, > Noddy. > > > > Which particular one did you have in mind? :D -- Posted at www.usenet.com.au
From: Noddy on 19 Jun 2010 06:36
"hippo" <am9obmhAc2hvYWwubmV0LmF1(a)REGISTERED_USER_usenet.com.au> wrote in message news:hvhsoq$rqf$1(a)news.eternal-september.org... > Which particular one did you have in mind? > :D All of them :) -- Regards, Noddy. |