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8

The diagram looks like the Fat Man bomb that was dropped on Nagasaki. The Wikipedia article gives lots of info on the design if you're intereted in pursuing it further. The casing is just to make it aerodynamically stable so it fell in a controlled way. The bomb itself is spherical so the case could be spherical as well if it weren't for aerodynamic ...


6

There will be no attempt to utilize the energy released from fusion reactions at NIF. NIF's goal is to demonstrate that a sustained fusion reaction is possible. Such a demonstration is termed "ignition" and there is a good chance it will be achieved within the next three years. The next step is a project called LIFE which involves a prototype power plant ...


4

I was going to comment, but am making it into an answer. The experimental proof that fusion works with small amounts of matter ( no need of gravity to work) is the H-bomb. The engineering problem is large and people are working on it with various designs. The world community has put its money on ITER which is currently being built in France. The design ...


3

There are no proofs, there are only disproofs. The history of fusion is littered with designs that seem promising on the back of the envelope, but upon closer inspection turn out to have unforeseen difficulties--usually some kind of instability, or energy loss mechanism. For example, in magnetic confinement devices, the strength of the magnetic field is ...


3

Lift is a function of the speed of the air from the leading edge to the trailing edge. In a flat turn, the inner wing is moving slower than the outer wing therefore there will be a difference in the amount of lift produced. But in fact, an airplane can not change direction by flat turning this way. Rolling into the turn by the use of the ailerons is the ...


2

Something to keep in mind is the difference between changing the direction that the aircraft is pointing, versus changing the direction that the aircraft is moving. In straight and level flight you can stomp on the rudder and fairly quickly cause the nose to point 5 degrees or 10 degrees away from where it was. But (at least initially) you will not have ...


2

Wifi is around 2.4GHz so a wavelength of around 12.5cm Anything metal with holes much smaller than 12cm will work - even a mesh. But if you don't have a parabolic dish, only a spherical one, you might do better with a can antennea see eg http://www.turnpoint.net/wireless/cantennahowto.html for details of the calculation


2

There's a beautiful book on the subject of aerodynamics, Stick and Rudder. Either the book you are reading is not very smart about how airplanes work, or you are mis-reading it. Normally, the way you turn an airplane is the same way you turn a bicycle, motorcycle, or high-speed boat. You bank or tilt the vehicle in the direction you want to go. Since you ...


1

The WiFi frequency range is pretty much the same as a standard microwave oven. The reflective coefficient of the metal mesh in the front door is above 99% and it contains no special materials. On the other hand the shape of the reflector has a large influence. So either you can follow Martin's suggestion of a can antenna, which is widely used or buy a ...


1

I've been thinking how one can try to measure it. I suggest the following setting. First one should find out the dependency of tap water resistivity on salt concentration. Likely it should be made by experiment rather than consulting tables because the results would depend on the tap water. Having done the first part, one can conduct the experiment itself. ...


1

Use a commercial blue dye in the tank, and flush until the blue color disappears. You can find the e-folding rate by eye. The amount of water removed per flush depends on the toilet, from memory, it's about .9 in a normal flush, so that 90% of the blue color is gone after one flush, so that you lose all noticible blue after about 4 flushes.


1

Your chamber's thermal cycling environment is indeed "very demanding". You have my sympathy... From O'Hanlon's A User's Guide to Vacuum Technology, Chapter 17, Joints, Seals and Components: Welds: It is important to make the weld on the surface which will be exposed to vacuum. If the weld is made on the atmospheric surface, a gap may be created which ...


1

I won't address the details of the fluid dynamics that cause the cage to produce noise because it is well out of my area of expertise. But I have performed an experiment in my office. The small desk fan I bought was too noisy. Since it lives on the top of a tall bookcase and well out of reach, I removed the cage completely. It is a lot quieter now. My guess ...



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