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Comment Re:They measured more "thrust" when turned off (Score 1, Informative) 532

And yet they admit there are some thermal issues in your cited article. "He also admits that there are still traces of contamination caused by thermal expansion in the system". It still worth noting that these are tiny forces being measured and it's on the order of experimental error rather than useful thrust.

Comment They measured more "thrust" when turned off (Score 0) 532

What should be most telling was that this "engine" produced more "thrust" when it was turned off than when it was turned on. That should tell you how stupid this thing is but everyone is so caught up in the "I want to believe" moment that they ignore all the warning signs.

The "thrust" measured by every study is so tiny that it's equivalent to the gravitational attraction of the contraption to your body. There are thermal effects that could explain this tiny thrust. So when the contraption was cooling off, the thermal effects were enough to push the air in a non-symmetric way that it produced a tiny push on the sensors. You could have measured more thrust just blowing on the stupid thing.

Comment Thunderbolt3 on reversible USB-C solved problem (Score 1) 566

The future is 40-Gbps Thunderbolt 3 on USB-C connectors. You have up to 100 watts of power, multiple DisplayPorts, multiple USB 3.1 ports, PCI-e, and potentially 10-Gigabit Ethernet flowing on the same reversible cable. Nobody cares about having a bulky RJ-45 connector once USB-C gets popular. Even today people can easily add Gigabit on their USB 3.0 ports.

Comment Re: What's the deal... (Score 3, Insightful) 262

Again, using human power to turn a generator to fill a battery is a fool's errand. You're better off doing opportunistic regeneration on downhill and letting the person rest. Forcing a rider to output an extra 50 watts so that you can collect 30 watts in the battery is just idiotic. But the point was that even without regeneration, a single 26550 battery @ 98 gram and a 100 watt motor @ 50 grams is more than enough to win a race.

Comment Re: What's the deal... (Score 3, Interesting) 262

Regen on flat pedaling is stupid and goes along the lines of a perpetual motion machine. Much of the energy you pedal into the motor is lost in the form of heat and you won't get out what you put in. Reg on downhill would work and you don't need a more complex motor. All Brushless DC motors can regen when they're being forced to turn.

Comment Re:Why this is special (Score 4, Informative) 133

WiTricity has been demoing the only feasible technology (resonant inductive power transfer) since 2009. They can actually reach out a few feet without worrying about getting blocked by clothing or body parts or orientation of the receiver. But the media has forgotten them in favor of utterly unworkable solutions like Ultrasonic Power Transfer which can't go through objects and require exact receiver orientation and alignment to work. https://www.ted.com/talks/eric...

The challenge is whether WiTricity can deliver useful range range and sufficiently shrink the receivers to be thin enough to be in a smartphone. Useful range is likely a few feet which means it's much shorter than a typical cable. We're also looking at a minimum of 50% losses which might be acceptable for a smartphone, but we know there are plenty of people who have no qualms charging their 400 watt HDTV or 40000 watt car like this.

The real revolution we're seeing in smartphone charging is USB-C with a higher Power Deliver profile. Next generation Samsung phones coming out can be charged in around 20 minutes which means a charge rate of 3C. Batteries can be pushed up to 5C to get charge times times down to 12 minutes which means 6 minutes can fill up most semi-discharged smartphones. Fast charging is far more useful than being stuck in a 3-foot area for 2 hours waiting for the phone to fill up.

Comment Re: What's the deal... (Score 5, Interesting) 262

A pro competitor at Tour de France averages 450 watts. Casual fit rider averages 220. That means having a mere half a horse power would let the casual rider win the Tour de France though you likely wouldn't be able to put in that much battery capacity for the entire ride unless you swapped the battery along the way. For competitive riders, just having a 100 watt motor that can turn on 10 minutes is enough to go from last place to first.

Comment How about sharing a little with your employees? (Score 1) 842

Notch's Mojang was supposedly different from your typical greedy corporation and it was more family. In the end he sold out and left all his employees hanging. Out of that $2500 million dollars, would it be so hard to allocate $50 million into a trust fund such that every one of his 50 employees could have an interest-only income of $50,000 per year indefinitely? Yet he couldn't even sacrifice 2% of his payout?

Comment Re:Magic Pill - Self Discipline (Score 0) 153

"what if we eat so much crap food that the wholesome hearty foods stop being produced"

There really isn't a clear line between "wholesome hearty food" and "crap food". The dosage is the problem and some foods like deserts, candy, and chips are just so calorically dense and so tasty that they're almost assured to be overeaten by the majority of people.

Comment Interviewer is extremely ignorant on power (Score 3, Informative) 92

At one point the interviewer asks "how much money you gonna save on electricity for 50 computers, $50/year"? It's clear he's never even attempted to do the math. An extra 100 watts in California is going to cost $314.91 per year at the typical rate (above baseline) of 35.949 cents per year. That's just the savings on one computer system much less 50 computers.

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