Fact or Fiction

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My physics teacher told me that:

If you had a F1 car, and you got it to 70 mph, you could drive it round the outside of a tunnel, and upside down. Because of the downforce. Any idea if this is true?
 
Soldato
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Although an F1 car does generate more downforce than the weight of the vehicle making such a stunt theoretically feasible, in reality you couldn't *actually* drive it upside down in a tunnel. The fluids would drain to places they're not designed to and something would soon break
 
Man of Honour
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A car and drive weighs around 500kgs or something so if the downforce produced is greater than that, which I believe it is, then yes.
 
Associate
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If the downforce is greater than the the weight of the car

Seems to be tricky to get exact numbers but some googling suggests at top speed the effective downforce is somewhere around 2000kg and an F1 car weighs 600-700kg.

Now to find a tunnel the right shape and test the theory!
 
Soldato
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Not too sure if 70mph is correct given the mass of the vehicle and the radius of the tunnel but in theory the centrifugal forces should be able to counteract normal gravity force and contact forces.
 
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He's talking about driving it upside down which has nothing to do with centrifugal forces. Unless he is in fact talking about doing loop-de-loops rather than driving down the tunnel :)
 
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Not too sure if 70mph is correct given the mass of the vehicle and the radius of the tunnel but in theory the centrifugal forces should be able to counteract normal gravity force and contact forces.

Doing it that way only requires a Toyota Aygo at 37mph
 
Soldato
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Is this actually true? 70mph seems a bit slow to be making over 605kg of downforce that would be required for a minimum weight F1 car.

I don't know how accurate the figures are but in LFS the Sauber can only produce ~245kg at 31m/s (70mph) with all the wing maxed. According to that, you'd need at least 110mph to make enough force.
 

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Doing it that way only requires a Toyota Aygo at 37mph

I wondered Years ago when I would meet my First Nanospider.
Initially I will be Polite & say Hi & welcome to OcUK but I Will be watching you, Any of that nanotech splitting into minnions infecting every ****** & I am calling the Brigade !!!
 
Caporegime
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Supposidly the gumbert can do it too? Though there aint a tunnel smooth enough to try it?
 
Caporegime
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As said, if a car can produce more force in downforce than its own weight, then at speeds at which it producing this downforce it can be driven on the top of a tunnel.

However, as said, the practicalities of such an experiment make it impossible to actually drive the car. If you could find a way to power an F1 car at the required speeds without it being tethered then it could be done.

TBH, im sure you could prove the concept using a small scale model and a wind tunnel. Making air travel at X speed is much easier than making a car travel at X speed upside down.

Its the same concept as flying. A plane generate enough lift to overcome its weight, and flys. Upside down an F1 car's downforce would be in the oposite direction and therefore be creating lift, and if would be 'flying' in the sence that it would be overcoming the force of gravity.
 
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Soldato
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@700kgs of downforce @ 70mph? i just cant believe that lol

edit: http://en.wikipedia.org/wiki/Formula_One_car

The front and rear wings are highly sculpted and extremely fine 'tuned', along with the rest of the body such as the turning vanes beneath the nose, bargeboards, sidepods, underbody, and the rear diffuser. They also feature aerodynamic appendages that direct the airflow. Such an extreme level of aerodynamic development means that an F1 car produces much more downforce than any other open-wheel formula; for example the Indycars produce downforce equal to their weight at 190 km/h (118 mph), while an F1 car achieves the same downforce:weight ratio of 1:1 at 125 km/h (78 mph) to 130 km/h (81 mph), and at 190 km/h (118 mph) the ratio is roughly 2:1.[5]

EEK!
 
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Soldato
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@700kgs of downforce @ 70mph? i just cant believe that lol

edit: http://en.wikipedia.org/wiki/Formula_One_car



EEK!

And you'd want to be doing a bit more than the minimum for a safety margin. You wouldn't want to accidentally slow down a bit on the roof of a tunnel, drop down to 80mph, then notice you barely had any friction to accelerate/steer onto the ground again! :eek:
 
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