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The people are the propellant!!!

What, they get out and push? Silly wabbit.

Are you an idiot?

Of course. Just why in the living shit are you worried about it Coward? If you are someone that has a bone to pick with me, use your real pseudonym. Then again, you think ultrasound will generate harmonics in a linear medium... quite a trick in itself...

There's a thing though. There will be people in the room. And unless ultrasonic imaging doesn't work, there will be lots of interesting reflections and harmonics as watts of power are bouncing into and out of people, and other objects. http://www.physicsclassroom.co...

http://www.asecho.org/files/EF...

And, therein lies my problem with any real wireless charging. Watts of power flooding an area. Not a Luddite, but I am reasonably sure that can't be good.

Are you an idiot?

Of course. Just why in the living shit are you worried about it Coward? If you are someone that has a bone to pick with me, use your real pseudonym. Then again, you think ultrasound will generate harmonics in a linear medium... quite a trick in itself...

There's a thing though. There will be people in the room. And unless ultrasonic imaging doesn't work, there will be lots of interesting reflections and harmonics as watts of power are bouncing into and out of people, and other objects. http://www.physicsclassroom.co...

http://www.asecho.org/files/EF...

Anyhow, good luck without your researchers.

What, all 50 of them in Silicon Valley? FFS, I didn't even RTFA but I got enough from the summary to understand that this is less than a rounding error compared to Microsoft's overall R&D and engineering staffs.

Also, can we make it Schnell's Law that anyone who mentions the Year of the Linux Desktop without irony has triggered Godwin's Law about the Occam's Razor of Linux zealots' Panglossian combination of The Seven UI Laws, the Joel Test and Newton's First Law of Motion? Unless of course they have done it as part of a Russian Reversal.

I could certainly stand to lose a bit of the snarkiness; I am about to start a job among engineers. You should probably review basic circuits though, because you are still misunderstanding something:

If you have a 12V battery, and a 12V bulb in series, you have a simple series circuit that works; but adding 3 more bulbs of the same type in parallel won't work (contrary to what the text taught) because now each of the four loads (bulbs) are only seeing 3 volts.

Parallel components have the same voltage difference applied across them. Adding a bulb to another in parallel will not affect the brightness of the original bulb (as long as the current is still low enough to consider the battery ideal). Both bulbs are as bright as the original bulb, and the battery is supplying to each branch the current it supplied to the original lone bulb. Adding 3 bulbs in parallel just adds additional bulbs that draw the same power as the original, and increases the total current (and power) drawn from the battery by 300%.

Adding the bulbs in series does what you describe. Perhaps that is what you are miscommunicating.

I checked through the first couple of google results until I found a good reference for you. Everything here is correct.
http://www.physicsclassroom.com/class/circuits/u9l4b.cfm

I only call this out because you criticize "teach the test" type education, which I do as well for good reason, but then you ironically illustrate one of the largest failures of this type of education. It breeds people who are very confident in an only partial understanding. To stick to my earlier example, it creates the sort of students who might take a lot of pride in correcting you about the start date of the civil war without even knowing what events started it.

Series and parallel circuits are very different, but there are superficial symmetries between the currents of one and the voltage drops of the other, and people often use these to remember the phenomenological behavior. It's the easiest way for most people to get a B on the relevant test. Doing it that way is not understanding; it is rote memorization, and can leave people susceptible to confusing two things that are very different.

Come back when you're ready.

If you drive with horizontally polarized sunglasses, you cut the glare from the road, but still get glare from the windshield. If you switch to vertical, you cut the glare from the windshield, but not the glare from the road. I don't want to see any reflected light.

It annoys me too, but for a different reason. The fact that things look bigger in water is completely irrelevant to the subject at hand - that is just an optical trick to our eyes (which are outside the water) when the water is contained in a round container (a flat container does not exhibit this effect!) and would make no difference to a lithography system.

Contrary to the parent comment's question, if the item is inside the water, the water is no longer acting as a lens - it is simply the refractive medium instead of air (or vacuum). To refract, you MUST have an interface between two substances with different refractive indices - water, air, glass, oil, vacuum, or even metal (for x-ray or gamma rays, for example).

The magnification of a lens is largely a function of the difference between the refractive indices.

Now diffraction is different - that's a function of waves bending around a barrier - like the resist patterns being used. It has NOTHING to do with an interface between two mediums (except the barrier).

Here's a great primer on Diffraction, Refraction, and Reflection.

Come on, this is elementary stuff. Sound consists of both compression and rarefactions of the air; the average pressure remains unchanged.

But do you have the right to accept the risk for everyone else on the road?

As I mentioned, stopping distance increases as the square of the speed. Did you know about P = M * V? The energy imparted by a moving vehicle increases with the square of its speed; so a car travelling at 40 mph will dissipate four times more energy in an impact than one travelling at 20 mph.

So not only are you increasing stopping distance and decreasing the reaction time threshold, you are increasing the force you'll impart when you hit something.

Maybe you haven't realized it, but saying "speed doesn't kill" is as useful as saying "guns don't kill people, people do." Whenever you exceed the posted speed limit on a section of road, you are increasing the risk for everone who may be using that road. You're increasing the possibility that you'll be killing cyclists, jay walkers, pedestrians, other vehicles, etc.

To argue that a behaviour which increases the force and stopping distance while decreasing your safe reaction time on a road is not insane, is equivalent to arguing that it's the ground's fault that people who jump off of tall buildings die.

The fact that "c" = "c" only in a perfect vacuum tends to escape most people.

Show them this. It makes more sense.

I've found the description at PhysicsClassroom to be useful for explaining light. Now, it's geared toward high school students, and as such is not strictly accurate (most notably, light is a transverse wave, whereas the picture seems to imply that it is longitudinal), but at the least it answers the often asked question of "why does light only travel at c in a vacuum". It's a good site overall, I'd definately recommend it.