Saturday, July 18, 2015

A Cynic's View of Tesla's Ludicrous Physics

July 17, 2015
Tesla Offers New ‘Ludicrous Mode’: Zero to 60 in 2.8 Seconds

Here is what we are told.

1. Tesla Chief Executive Officer Elon Musk introduced a new “Ludicrous Mode” for the dual-motor version of the Model S during a call on Friday, allowing the all-electric sedan to go from zero to 60 miles per hour in 2.8 seconds.

2. Ludicrous Mode “is an extension of Insane Mode,” Musk explained. With acceleration of 1.1 Gs, “it’s faster than falling.”

Here is what we know.

3. v = at.

4. g = 32.174 feet per second per second.

5. 1 mile = 5,280 feet.

6. 1 hour = 3,600 seconds.

7.  A car accelerating at g can go from zero to 60 mph in 2.735 seconds.

60 = 32.174 x 2.735 x 3600 / 5280

8. A car accelerating at 1.1g can go from zero to 60 mph in 2.486 seconds.

60 = 1.1 x 32.174 x 2.486 x 3600 / 5280

9. If it takes 2.8 seconds for a car to go from zero to 60 mph then it isn't accelerating faster than gravity, and therefore certainly cannot, on average, be accelerating at 1.1g.

10. In sharp contrast to creative accounting, creative physics can be very easy to spot for those who bother to look.

11. I must be cynical because when given the choice of trusting the numbers or verifying the numbers, I seem to always prefer the latter.

12. Oscar Wilde once wrote that a cynic is a man who knows the price of everything, and the value of nothing. I know the market price of Tesla's stock, but, for the life of me, I have no idea what its market value should really be.

13. Oscar Wilde also once wrote that a sentimentalist is a man who sees an absurd value in everything and doesn't know the market price of any single thing. One could easily imagine a scenario where many stock market mutual fund participants are sentimentalists. Heck, under the right conditions, they might not even know the market price of any single stock they own. What might those conditions be? 6+ years of ZIRP and a sentimental belief that the Fed has permanently put an end to recessions? Call me cynical, but that sounds just about right.


Troy said...

I was just thinking yesterday how rooftop PV and EV have really started to 'mature' as mainstream technologies after being crude pipe-dreams 20 - 30 years ago, and how AV (autonomous vehicles -- we still need an acronym for these actually) and how MT (machine translation) is the next batter up.

I housesit for an AAPL zillionaire in Santa Cruz occasionally and he's let me use his EVs, he had a Leaf for a year, and that was OK but range was a bit tight for normal longer-range trips, like to Mountain View or Monterey, places less than an hour away.

He replaced that with a an EV Toyota Rav4, which has the same drivetrain as a Tesla apparently. Sucker's awesome. Zero range anxiety for these hour-long trips now.

He sells rooftop PV to PG&E by day and his EV charges overnight at very cheap rates. California's got 3GW of PV plant now which really helps with the supply situation, though demand peaks in the early evening when it begins to tail off.

Back in 2000 I actually bought my Miata with the explicit intention of converting to EV by now, but technology has moved a bit slower than I was expecting then. Plus I had to put a new engine in it in 2009 which pushed any replacement idea back a decade anyway.

Troy said...

On a lark I tried to get DSR working on MAME/MESS

is the demo disk, the actual X68000 app requires making a user disk and I don't want to muck with that.

Still, pretty amazing actually running something I first saw in a Japanese game magazine exactly 25 years ago (when I was an intern at MicroProse).

What kills me is I saw the future then, but SSI's president did too and he actually took the ball and scored, with Panzer General.

i5-4690K utilization is 60% of one core to run the X68000 emulation, not bad.

Have had my FrankenMac running 10.11 for a month now, no complaints. Thing is dead silent and I saved over $1000 by not having to get an iMac with its bundled 27" display, as I still had a perfectly good 24" display from my 2008 purchase.

Stagflationary Mark said...


Zero range anxiety for these hour-long trips now.

I totally understand the concept of range anxiety. My first mower was battery operated. I bought it in 1997 when I bought my first (and only) house.

The first couple of years the mower worked great, I live on a third of an acre. Had the range to mow both the front yard and the back yard no problem. Loved it!!

The next couple of years I could only do one or the other before needing a charge. No longer loved it, but still kind of liked it. I mean it was still quiet and fume free which was nice.

And then... well... the serious range anxiety began to set in. No longer liked it at all, lol. Sigh.

Still, pretty amazing actually running something I first saw in a Japanese game magazine exactly 25 years ago (when I was an intern at MicroProse).

Very amazing. It would certainly not be easy to get the games I worked on in the mid-1990s to run on a modern computer. Not easy at all.