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Roughly, rocket's final speed is ~Ve / (propellant portion of the rocket). If you through in this condition, chemical propulsion may not do.

It was a long time ago when I calculated the speed gain vs energy spent by the rocket. I reworked that and it shows that the ratio is decreasing as the speed of the rocket increases compared to that of exhaust. Sorry I was not very clear.

You are right. The rocket still gains speed.

One thing that needs to be considered is your speed vs. that of exhaust. Once you reach the speed of exhaust, it does not help you very much. You need the speed of exhaust as fast as possible. Ultimately, you want to use ion engine or photons to propel your rocket to go very far.

It probably depends on how hot you can heat the gas. Roughly 0.5 * M * V^2 ~ k * T. k is the Bottzmann cost. T is temperature. M is the mass of the molecule. V is the velocity. By the way, the fastest exhaust out there is photons.

Maintenance? Taken today.

Taken today

It seems that Tesla's announcement about next motor without rare earth elements surprised experts. https://spectrum.ieee.org/permanent-magnet-tesla

For a rotating space station, to have gravity, period T = 2 * PI * sqrt( (radius in meters) / 9.8). For radius 980 m, T is about 63 sec.

Construction pictures taken today.

Interesting. So after using up 8% of fuel, assuming most of the weight is fuel, the thrust to weight ratio is about 1.3.

A few cars charging there earlier today.

Construction fence is gone. Transformer is there.

Construction in progress.

There is a transformer at that location. Sorry, no pictures.

Cabinets are on the ground floor. I did not see a pad for transformer.

600 cars is too good to be true. :) 3000kwh / 50 kwh = 60

These spikes around bright objects are there due to the shape of finite size "aperture". When light pass by objects, part of it diffracts. Circular apertures create circular diffraction patterns overlayed to each bright points. In this case, dominant pattern is probably from the shape of the...

https://www.nasa.gov/press-release/nasa-s-webb-reaches-alignment-milestone-optics-working-successfully First fully aligned image!

In one of the webcasts, someone mentioned that the temperature reading is more or less consistent with their simulation. I assume the heat shields are OK.

Santa Clara County Sewage Monitoring: https://covid19.sccgov.org/dashboard-wastewater Not as dramatic as Boston, but cautiously optimistic.

Wow! They won't allow @RubberToe to take a rest.

NTSB Update today: https://www.ntsb.gov/news/press-releases/Pages/mr20211021.aspx Both driver and passenger seats were occupied at time of crash Damage to steering wheel was due to an impact. The vehicle reached a speed of 67 mph during the 5 seconds leading up to crash.

It may be connected to the mechanical lock that will lock the CCS plug into the adaptor when pressed.

Sorry. I wasn't prepared to take a picture.

You can clearly see some construction equipment and a few V3 cabinets from north bound 5.

It is not at the SC site, but North Coast Brewing Company has good beer and food.

This is from Nature article, depicting messy IP connections related to mRNA vaccines. I was surprised to see Tesla here.

Tom mentioned that his car is only 3 weeks old. Can it be that there is some difference between old and new cars?

Tom Moloughney says his unit works. CCS1 To Tesla Adapter Finally Available For North American Market

This worked for me. The car turned on by itself in less than 5 mins after step #1. I rebooted twice after that.

Temperature change can be a factor, too. We are having unusually warm weather recently.

Have you tried to fit the curves with exp(-(miles driven)/A) * exp(-(battery age)/B) * (initial capacity) ?

I agree that this will be the most efficient configuration. When you apply large torque, you want it to rear wheels, not to the front wheels.

For PMAC motor, larger torque means stronger magnet, and this increases magnetic loss when the rotor spins. To reduce loss, you do not want the PMAC motor too powerful.

AC induction motor does not dissipate power while spinning when it is not energized, but PMAC motors does. Spinning magnets magnetize iron and there is hysteresis loss. So dual motor with PMAC is not as straightforward as with AC induction motor as MS has.

Weight difference between full and empty battery is not that much. :-) You can use E = m * c^2 to calculate. E = 7.5e4 wh * 3600 J/ wh = 2.7e8 J m = 2.7e8 J / (3.0e8 m/s)^2 = 3.0e-9 kg

Loss is proportional to resistance not to square of it.

Well, the race is on! Who's going to be the first to get there in Model S?

I talked to a ranger there couple of years ago. According to him, one of the issues of putting chargers there was that they were not getting enough power into the valley.

There is another possibility: I do not know how good the winding machines are, and how tight they wind the wire. Tesla did not say one motor has more windings, but did say it has less resistance. Maybe manual winding uses shorter wire to achieve same number of windings.

One more nice item to have is the heated windshield (HWS). The windshield in RAV4-EV has resistive heating film on it. Very fast and effective during damp season. I rarely use the heat pump. I usually use the HWS and heater in my seat in winter. Young

I think this is due to the fact that Focus EV was initially designed for Hydrogen Fuel Cell vehicle. That bump is where the high pressure tanks is supposed to be.

Chevy Volt uses PM motor, EV1 used induction motor.

You can put more than 10,000 of 18650 cells into EV1 battery compartment. And this will weigh less than the original lead battery pack. EV1 could drive more than 6miles per kwh from battery. 3.1Ah * 3.6V * 10000 * (6miles/kwh) > 660 miles.

Rav 100k I am one of them.

Mine is at 107k miles.

I do not think that is quite true. There IS such a regulation from CARB for hybrid cars that need to be classified as such for ZEV credits. I do not think it applies to EVs.

As a driver of RAV4-EV for 8 years, my opinion is different. As range anxiety is overcome, people will realize that cost and weight associated with long range battery pack is not worth it, as long as level 3 or fast charging is available everywhere. I think Nissan has a right idea.

The cells are kind of expensive now, more than $10 in the internet.