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

ethz.ch

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

#301

Post by codethief »

jameshart wrote: post #284
codethief wrote: post #267

Earlier quoted context omitted.

Hmmm, from a Newtonian perspective I would have argued (or at least my personal impression is) the only thing we actually perceive is force (i.e. acceleration). All the situations you described are just (higher-order) changes of acceleration and even if you give them a name: At the end of the day, the only thing that matters to our bodies is the force.

Sure, but my argument is that you only really take note of changes in the acceleration you experience. Yes, your internal sense of ‘which way am I accelerating’ is the sensor you’re using (also ‘which way and how hard are my limbs being pulled’ and ‘how much force am I feeling in my joints and on the parts of my body that are touching the objects around me’) - but when those all indicate a generally constant vector w…

Interesting thought but I'm not entirely convinced yet: 10m/s² down (along your body axis) is not the same as 10m/s² in any other direction. I would assume the body is perfectly able to distinguish between those.

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

#302

Post by AtlasBarfed »

wherefour wrote: post #289
AtlasBarfed wrote: post #251

Earlier quoted context omitted.

Fine. At the time when it ran that time it was the fastest, and faster than practically every sports car ever made. The nurburgring is about the most sports car track ever made. I don't really know how to measure anything about a car's sportiness other than its speed around the track generally agreed to be the most "Gran Turismo" style. If you want your own personal gatekeeping standards for "true sports car", whatev…

> Fine. At the time when it ran that time it was the fastest, See here: https://www.hotcars.com/fastest-sedans-around-the-nurburgrin... And join with the list here: https://en.wikipedia.org/wiki/List_of_N%C3%BCrburgring_Nords... All five sedans that beat the Model S around the Nürburgring drove their laps earlier. The Plaid has only ever been the sixth fastest sedan around the 'ring. Which is excellent, but not what…

Hm I think you're right. I must have been thinking of Laguna Seca.

Of course, I'm assuming THAT isn't a "real sports car course" either.

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

#303

Post by wherefour »

AtlasBarfed wrote: post #302
wherefour wrote: post #289

Earlier quoted context omitted.

> Fine. At the time when it ran that time it was the fastest, See here: https://www.hotcars.com/fastest-sedans-around-the-nurburgrin... And join with the list here: https://en.wikipedia.org/wiki/List_of_N%C3%BCrburgring_Nords... All five sedans that beat the Model S around the Nürburgring drove their laps earlier. The Plaid has only ever been the sixth fastest sedan around the 'ring. Which is excellent, but not what…

Hm I think you're right. I must have been thinking of Laguna Seca. Of course, I'm assuming THAT isn't a "real sports car course" either.

People race motorcycles at Laguna Seca. Several of them are faster than the Plaid. Are they sports cars too?

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

#304

Post by jameshart »

codethief wrote: post #301
jameshart wrote: post #284

Earlier quoted context omitted.

Sure, but my argument is that you only really take note of changes in the acceleration you experience. Yes, your internal sense of ‘which way am I accelerating’ is the sensor you’re using (also ‘which way and how hard are my limbs being pulled’ and ‘how much force am I feeling in my joints and on the parts of my body that are touching the objects around me’) - but when those all indicate a generally constant vector w…

Interesting thought but I'm not entirely convinced yet: 10m/s² down (along your body axis) is not the same as 10m/s² in any other direction. I would assume the body is perfectly able to distinguish between those.

Yes, you know if you are standing up or lying down. But your body doesn’t interpret either of those sensations as movement.

If you flip from one to the other suddenly, your brain figures out ‘we’re rotating’ pretty quickly though.

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

#305

Post by namdnay »

The_Double wrote: post #271
namdnay wrote: post #194

Earlier quoted context omitted.

Modern motors get lighter in part because they can offer lower torque with a smaller rotor but compensate with higher rpm. That’s not possible for a hub motor

The hub motors on the car in the OP run at ~24k RPM (faster than any production electric car AFAIK) and have a multistage planetary gearbox for reduction. Pretty much all top Formula Student cars now use hub motors. Mainly for packaging reasons. Putting the motor in the unused space in the wheel means you can make a smaller chassis and have more space for wings and underbody aero.

wow, interesting! i didn't imagine you could fit the "gearbox" in the hub too

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

#306

Post by alwaysrunning »

onychomys wrote: post #197
alwaysrunning wrote: post #142

As someone who grew up racing go karts and still enjoys motor sports (mostly F1), the problem I have with e-racing is the lack of sound. The winding noise they make just isn't adequate and really puts me off to the racing.

On the other hand, the Formula-E cars sound exactly like TIE Fighters, and that's awesome.

Very true.

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

#307

Post by tzot »

lucgommans wrote: post #71
tzot wrote: post #22

Earlier quoted context omitted.

$ units You have: 100 km per hour / 0.956 sec You want: gravity * 2.9629132 / 0.33750567

Protip: no need for a dedicated unit conversions utility, this awesome calculator has it built in: $ apt install qalc $ qalc > 100 km/h / 0.956 s to gee (100 * (kilometer / hour)) / (0.956 * second) = approx. 2.9629132 gees

The word “dedicated” does not correspond to verifiable facts, since `units` can do dimensionless / unitless calculations just fine; it is already a calculator with units built-in, and the example you provided only intensifies the impression that `qalc` and `units` are equivalent.

IMO a proper pro-tip for `qalc` would need an explanation why one should prefer it over `units`.

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