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New world record with an electric racing car: From 0 to 100 in 0.956 seconds

ethz.ch

121–130 of 307 posts

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#122

Could we maybe change the title here and change it to 100mph? I realize this is the original article title but EV + 0 to 100 led me to believe the article was talking about battery charging speed.

But 100mph (or kph) is also a way to describe charging speed.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#123

Earlier quoted context omitted.

radicalbyte, you're absolutely right that the use of fans in Micromouse increases the traction, and therefore the speed at which the maze is solved. Suction allows for impressive performances. However, a small caveat that might be worth considering is that while the suction indeed increases speed, it might be more accurate to say that it primarily improves acceleration instead of car speed: The issue often lies with…

Speed = ∫(acceleration) dt

Sure, but once you have speed you can use aerodynamics to get grip (e.g., F1 cars). So this is really only relevant if you need acceleration from low speed.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#124

Earlier quoted context omitted.

Still wouldn't get close (in the performance sense, where the effort to time gained is logarithmic in nature). This car weighs 309 lbs. The batteries alone in a Model S weight 1200 lbs.

True, but this car has low 300s HP, no torque mentioned that I saw. The Tesla is over 1K HP and torques. The Teslas, for road cars, are pretty stunning for acceleration. Agreed that it's not going to reach this level of 0-100 performance, but it sounds like it can get shockingly close. I've driven Porsches on the track, and the Tesla Model S Ludicrous loaner I had for a few days is startlingly fast. Fast enough that…

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Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#125
post #87
post #4

The impressive thing to me is the level of traction needed to do something like this. It seems they're taking old tricks and building a "sucker car". https://www.roadandtrack.com/motorsports/a32350/jim-hall-cha... Still neat stuff. Race sanctioning bodies will need to update their rules or these will just be one off bragging rights.

Interesting. This is a Formula Student car, the european version of the Formula SAE. Powered ground effects were banned a long time ago in Formula SAE, but it seems like Formula Student does allow them.

It was disallowed for many years but is re-allowed since the 2022 season

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#126

How many football fields of acceleration is this?

It's *roughly* the gravitational acceleration at the surface of an Olympic-size swimming pool of electron-degenerate matter from a white dwarf star. Hope this helps! (Note: the swimming pool has collapsed under its own weight and is now a sphere).

A white dwarf's density is apparently around 1e9 kg/m³. Olympic swimming pools at 50m*25m*2m * 1e9kg/m³ would have a weight of 2.5e12 kg. As a sphere, the radius is (solving: volume_of_sphere = 4/3×π×radius³)

    $ qalc 50m*25m*2m = 4/3*pi*x^3
    (((50 * meter) * (25 * meter) * (2 * meter)) = ((4 / 3) * pi * (x^3))) =
    approx. (x = 8.4194515 m)
Gravitational acceleration (for a point mass) is: the gravitational constant, multiplied by the mass, divided by the radius squared, and we want the result in Earth gravities:

    $ qalc G * 2.5e12kg / 8.4194515² m² to gee
    (newtonian_constant * ((2.5 * (10^12)) * kilogram)) / ((8.4194515^2) * (meter^2)) =
    approx. 0.24 gee
You're only one order of magnitude off — if this is correct, which I am really not sure about!

Sources: https://en.wikipedia.org/wiki/White_dwarf · https://en.wikipedia.org/wiki/Olympic-size_swimming_pool · https://duckduckgo.com/?q=volume+of+a+sphere&ia=answer · https://www.wolframalpha.com/input?i=surface+gravity+calcula...

What I'm even less sure how to calculate is whether an 8-meter sphere can be that heavy. Uranium is ~2e4 kg/m³, but under its own gravity, things shrink until they reach black hole status (infinite smallness; perceived size coming from its event horizon). Basically I'd want to turn the above 1e9kg/m³ into an unknown, but what's the formula for mass given your specified radius and gravitational acceleration? TBD

I'm really curious if this was just a few words strung together and it happened to come out to within one order of magnitude by pure coincidence, or if (how) you calculated this!

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#127
post #4

The impressive thing to me is the level of traction needed to do something like this. It seems they're taking old tricks and building a "sucker car". https://www.roadandtrack.com/motorsports/a32350/jim-hall-cha... Still neat stuff. Race sanctioning bodies will need to update their rules or these will just be one off bragging rights.

These cars stem from the Formula Student, which since 2022 has re-allowed the previously forbidden "powered ground effect".

But this car has an upgraded battery and powertrain beyond what the rules allow and they maybe also use tire warmers and potentially rubber/glue on the launch surface/tires

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#128
post #68

Impressive but for reference, about half the acceleration of a Top Fuel dragster, which are also still getting faster. Here's Brittany Force who holds the current records (fastest time, fastest speed): https://www.nhra.com/news/2022/brittany-force-sets-national-... 0 to 338.43 mph in 3.665 seconds over 1000 feet. (The cars got too fast for 1,320 feet and have been racing 1000 feet since 2008.)

The dragsters need to have a complete engine tear-down after nearly every run, regularly explode in a giant ball of flame, etc.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#129

Out of curiosity, what's the point of a driver in something like this besides to have a human in the vehicle adding weight? Are they doing much? Serious & maybe very ignorant question. - Edit - For clarification, my reason for asking was due to this occurring in less than 1 second. I don't understand what the driver does as I'm assuming they have no gears to shift or turns to make.

AMZ's cars are also capable of autonomous driving (they were actually one of the top teams in the autonomous categories for the last couple of years).

I assume it's just a requirement for this Guiness record category, or they didn't want to bother with all the software.

Re: New world record with an electric racing car: From 0 to 100 in 0.956 seconds

#130

Earlier quoted context omitted.

I assume it's because racing, as a sport, is a lot less interesting without the variable of a human with particular skills operating the vehicle. I doubt crowds would be as interested in watching cars race on autopilot, though it'd still be kind of cool, I guess.

> racing, as a sport, is a lot less interesting without the variable of a human with particular skills operating the vehicle. If full self-driving gets much better, I think it could be fun to see this happen. It would be like a hackathon with teams swapping out and improving on strategies through laps. The qualifiers could happen on electric miniatures then the final round would get a full car to race on a track.

The racing formula this is from, Formula Student, actually has a driverless competition as part of it. It's pretty fun, but also harder than one would think, still.
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