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Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

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Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#101

Post by Dylan16807 »

jackmott wrote: post #42
LeifCarrotson wrote: post #39

Earlier quoted context omitted.

> High school friction is wrong. No, it's at least mostly correct. High school friction says F = mu * W Where F is the output force, mu is the coefficient of friction, and W is the normal force (typically equal to the weight). If it's failed you, it's failed in failing to mention that the tire-road interface can have a coefficient of friction greater than one, and in failing to mention that the normal force can be in…

High school physics tends to claim that the coefficient can't be greater than one. Source: note all the people here who thought it couldn't be greater than one.

Mine never implied that, and I could have easily disproved it with the grippy pads on my giant calculator.

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#102

Post by grkvlt »

jaredraby wrote: post #38
gravypod wrote: post #37

Earlier quoted context omitted.

The reason why an EV would outperform most motors is mutli-fold 1. No cold starting. The engine is on as soon as you push power in. 2. Equal torque at all speeds 3. The lack of a need for a transmission. All "gears" can be controlled by how much power you're feeding The EV is more like a solid state transistor verses a relay. They do similar things, they're good for different applications, but the transistor has some…

It's not equal torque at all rpm.

So, torque is defined as Tau = P / omega where P is power, omega is angular velocity and Tau is torque. In an ICE, P varies a lot with rpm (i.e. angular velocity) giving a sort of inverse-bathtub curve whereas in an electric motor the power curve is pretty much flat. In an ICE at startup (so essentially zero plus epsilon rpm or angular velocity) the power is quite low, so torque is also low. In the electric motor the power output will be essentially whatever it is rated at, so the torque will be highest at this point, getting lower as rpm (angular velocity) increases.

For a much better explanation than I can provide, see https://en.wikipedia.org/wiki/Power_band#Electric_Motors

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#103

Post by FireBeyond »

mikeash wrote: post #68
semi-extrinsic wrote: post #51

Earlier quoted context omitted.

> It also depends on how you define "Worlds fastest car" ... and here they defined it so the P100D is the fastest. Welcome to the tautology club. Meanwhile, Wikipedia has three cars above the P100D on its quickest 0-60 list: the Porsche 918, the LaFerrari, and the Bugatti Veyron. https://en.wikipedia.org/wiki/List_of_fastest_production_car... Note also that Tesla has also been called a bit "optimistic" with their 0-6…

Wikipedia still shows the old 0-60 time for the P100D. At 2.4 seconds, it will be ahead of the Veyron, even with the LaFerrari, and behind the 918. And Tesla only compares with cars currently in production. The LaFerrari and 918 are not. Definitely some definitional tweaking to get the "right answer," but not quite a tautology.

"the old 0-60 time"

The _current_ 0-60 time, you mean. Especially with this:

"And Tesla only compares with cars currently in production."

considering this is only a teaser tweet, there's a slight hint of irony there. "Currently in production" is also very different from "fastest production cars". Very selective.

This happened last time Tesla announced something like this - people fell over themselves to install it in the Wikipedia page for fastest production cars. Even though it was: 1) not yet available, 2) not verified, and 3) described even by Tesla themselves as an "expected result". i.e. a press release.

When that didn't work, they took to the page to add a new column to the list of accepted results, to add, effectively "manufacturer projected results", with the end result looking entirely silly and forced - a top 20 chart with Tesla being the only one to have a result in a "not real, not yet" column.

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#104

Post by FireBeyond »

cynix wrote: post #20
Shivetya wrote: post #11

At what battery percentage? Let alone, why? I want range, range, and more range. I could not give a damn about how fast I get to the next stop light or supercharger. Brag when you get 500 miles a charge, even fifty miles more range is more impressive than a tenth of a second off your acceleration "with a full charge"

> I want range, range, and more range. I could not give a damn about how fast I get to the next stop light or supercharger. You're not the target audience for their top-of-the-line P100D. It's aimed at people who would otherwise buy Bugatti Veyrons, Ferraris, etc., and range probably doesn't even come up in their decision making process. The Veyron has a range of 50 miles at top speed, for example.

No... it's not.

People in the market for supercars at up to $2MM are not in the same market as the P100D.

Range may not come up as an issue, as you say with the Veyron. The fact that the Veyron can actually accomplish it's top speed for those 50 miles will, however. Just like Tesla cannot complete a lap of a race course at top speed without thermal shutdown / limiting.

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#105

Post by mikeash »

FireBeyond wrote: post #103
mikeash wrote: post #68

Earlier quoted context omitted.

Wikipedia still shows the old 0-60 time for the P100D. At 2.4 seconds, it will be ahead of the Veyron, even with the LaFerrari, and behind the 918. And Tesla only compares with cars currently in production. The LaFerrari and 918 are not. Definitely some definitional tweaking to get the "right answer," but not quite a tautology.

"the old 0-60 time" The _current_ 0-60 time, you mean. Especially with this: "And Tesla only compares with cars currently in production." considering this is only a teaser tweet, there's a slight hint of irony there. "Currently in production" is also very different from "fastest production cars". Very selective. This happened last time Tesla announced something like this - people fell over themselves to install it in…

One of the meanings of "old" is "former or previous."

And I see no irony. The teaser tweet is stated using the future tense. It will be the fastest car in production once it comes, unless some other car maker has a big surprise between now and then.

As for the Wikipedia stuff, I offer no defense of it, but I'm not surprised. Wikipedia suffers from plenty of fanboyism.

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#106

Post by eridius »

threatofrain wrote: post #98
Someone1234 wrote: post #72

It wouldn't surprise me if they legislate maximum acceleration in the next ten years. Zero to sixty in 2.5 seconds is fun, no doubt about it, but it is fun on a racetrack. You can go on YouTube right now and find dozens of people utilising Tesla's existing "ludicrous mode" on public streets. And here's the thing, if people want to endanger their own lives that's fine. But they aren't just endangering their own lives,…

But isn't banning top velocity on the manufacturer-level much more lower-hanging fruit than banning top acceleration? Just make it so your vehicle can't even go over legal speed limit. It should be clearer to us today how speed kills in some of the most wide-reaching ways. Velocity is a much more obvious policy knob to tune for the goal of less vehicular deaths and injuries.

Not being able to go over the legal speed limit can be dangerous (e.g. if the other cars on the road are, and you're not, you could actually be driving relatively slowly enough that it's unsafe, and you can even technically get a ticket for that under the right circumstances).

Similarly, in most places, speed limits are actually a little lower than they would be in the ideal world where everybody obeys them, to account for the fact that most people actually go a bit over the speed limit. And there are still highways that have absurdly slow speed limits that date back to the 1973 oil crisis (federal law set a maximum speed limit of 55mph, and not all highways have recovered from that yet).

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#107

Post by mirimir »

jameshart wrote: post #47
mirimir wrote: post #31

Earlier quoted context omitted.

With rear-wheel drive, acceleration transfers most of the vehicle weight to the rear wheels. That's why funny cars do wheelies. That doesn't work so well for front-wheel drive, so those vehicles can't accelerate as quickly as rear-wheel drive vehicles. With four-wheel drive, weight transfer cuts both ways, but more rubber on the road helps, for sure. Low center of gravity helps too, I think.

With wheels on the bottom of the car acceleration transfers weight to the rear axle. The forward forces on the car body are below the CG so produce a net rearward tilting torque.

Yes. But my point is that, with front-wheel drive, that transfers weight away from the driven axle.

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#108

Post by UnoriginalGuy »

nrb wrote: post #99
Someone1234 wrote: post #87

Earlier quoted context omitted.

That "nanny state nonsense" witnessed road deaths fall from 25 per 100K in 1930 to 10 per 100K since 2010. We've halved road deaths per every 100K of population! I'll take my nanny state nonsense where people are still alive, over the libertarian wet dream where they're dead. I really think it boils down to that some people value their own personal enjoyment over other people's safety. The sad truth is that you could…

Uhh... I'm pretty sure vehicle safety improvements have more to do with that than anything.

Which are enacted largely through legislation.

Re: Tesla ‘Easter Egg’ Makes the Fast-Accelerating Model S Even Faster

#109

Post by pascalxus »

Someone1234 wrote: post #72

It wouldn't surprise me if they legislate maximum acceleration in the next ten years. Zero to sixty in 2.5 seconds is fun, no doubt about it, but it is fun on a racetrack. You can go on YouTube right now and find dozens of people utilising Tesla's existing "ludicrous mode" on public streets. And here's the thing, if people want to endanger their own lives that's fine. But they aren't just endangering their own lives,…

Unthought, kneejerk reaction.

Driving while eating a cup noodles is extremely dangerous too, I don't see any laws on the books against that.

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