Actually the only kind of dirty bomb that a terrorist group has a real possibility of making would not remain dangerously radioactive for more than a year or so. Of course it may require demolishing heavily contaminated buildings but the point is that it won't kill many people because you don't get a dangerous dose unless you -stay there- for long periods of time. However any kind of dirty bomb is highly effective at causing panic.
Why do people look down on mechanics, builders and plumbers? I honestly don't see why computer technicians should be treated any differently to them (and I am working my way through university by selling and repairing computers) but I do think people should have a lot more respect for these professions.
Fixing a car, computer or cracked pipe takes skill and experience. These people do an honest job, often more honest than a high-priced lawyer or accountant, but they're treated like scum for some reason I've yet to understand.
Of course there are some people who do a lousy job but that applies just as well anywhere else.
Frequency refers to how often the polarity of the magnetic field changes, i.e. north pole reverses to become south pole and vice versa. It's very similar to AC with electricity, and in fact electromagnets work on some of the same principles as radio transmitters.
Usually electromagnets are of lower frequency than radio because the core (e.g. iron or ferrite, they are used to greatly boost the power of the magnet) takes some time to change polarity. In this case they've managed to get it switching trillions of times a second which probably has some applications in research.
Someone with better experience than I can explain the difference between traditional magnetic fields and radio waves, but as I understand it, radio waves are sort of like a magnetic field creating another magnetic field of opposite polarity which creates another, etc... electric fields are involved too. Radio waves in general reach much further than near-field magnetics.
Have you ever actually tried it? This really doesn't work. The first time I blew up an egg in a microwave I thought of this and set a heavyish plastic jug over the egg. One minute later and the force of the explosion blew the door of the microwave open and slammed the jug against the opposite kitchen wall. Seriously, there's a lot of power in these things.
Actually most of the later Russian landers survived for at least an hour, by which time their motherships which provided communication relay had gone out of range. Of course this doesn't mean they lasted days or weeks but doing that is certainly possible. Getting an actual rover to work would be much more difficult.
Please provide some evidence that cell phones are producing or routing ionizing radiation, viz. UV and higher "through your ear and into your skull". Alternatively provide evidence that the microwave frequencies used by cell phones are harmful in any way other than direct heating, which is negligible at these power levels.
IIRC near-field effects commonly called 'magnetic fields' drop off as the cube of the distance, but far-field effects i.e. radio waves, microwaves etc drop off as the square of the distance - explaining why radio transmissions can cover vast distances but two bar magnets won't attract past a few cm.
Re:how the communications are handled
on
A Deep Space Primer
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· Score: 2, Informative
I thought of that too;) Sadly, it doesn't work. The balls at the far end of the tube don't 'know' to move until the signal, in this case a pressure wave, reaches them. In fact in this case the limit is the speed of sound in the ping pong balls.
I hope we can beat relativity some day. At the moment though, it doesn't look promising.
Just FYI - the capsule probably leaked very very small amounts of tritium if any at all. The reason it got dimmer over 12 years is that the halflife of tritium is 12.3 years - in other words have of the atoms will have decayed in 12.3 years, so it will only be emitting half as much radiation to get turned into light. It's kind of neat to see that as something you visibly noticed!
Yes.. I'm talking about orders of magnitude here. For us to use up say 1% of the Moon's mass, we would have to mine 7.35x10^20 kg. That is, 735,000,000,000,000,000 tonnes.
For every man, woman and child currently alive in the world (and even that number is too big to comprehend, for me anyway), mass of moonrock equivalent to the weight of 365 Empire State Buildings would have to be removed from the moon. All that just to change its mass by 1%.
Even if that mass were coal, not H3 which stores many many times more energy, it would last us for millions of years. By which time we will have something else for an energy source.
In conclusion, unless a deliberate effort was made, there is absolutely no way we could affect the mass of the moon enough to cause a noticeable difference in tides or anything else.
P.S. Even if the mass were to change, the Moon would simply shift into a different orbit. It would not "spiral away from the Earth" or crash into us. Orbits, though complicated, are not delicate things. Yes they are in balance, but changing a factor won't just make the object fall out of the sky.
Ignorant. The moon is really fucking big. There's no possible way we could remove enough mass to make a measurable difference. Besides, it's already moving away from the Earth at a rate of about 1 inch per year.
OTOH I don't see working fusion reactors turning up any day soon either.
They exist. Can't find the link now but I priced one up a couple months ago for a system and the cheapest was around $60 for a 4-port SATA card with hardware RAID 5 among others.
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Actually the only kind of dirty bomb that a terrorist group has a real possibility of making would not remain dangerously radioactive for more than a year or so. Of course it may require demolishing heavily contaminated buildings but the point is that it won't kill many people because you don't get a dangerous dose unless you -stay there- for long periods of time. However any kind of dirty bomb is highly effective at causing panic.
A lot of Cold War SAMs had the option of nuclear warheads.. that should certainly take out any blimp.
Fixing a car, computer or cracked pipe takes skill and experience. These people do an honest job, often more honest than a high-priced lawyer or accountant, but they're treated like scum for some reason I've yet to understand.
Of course there are some people who do a lousy job but that applies just as well anywhere else.
I hope that most people's brains would be smaller than chimpanzees!
Usually electromagnets are of lower frequency than radio because the core (e.g. iron or ferrite, they are used to greatly boost the power of the magnet) takes some time to change polarity. In this case they've managed to get it switching trillions of times a second which probably has some applications in research.
Someone with better experience than I can explain the difference between traditional magnetic fields and radio waves, but as I understand it, radio waves are sort of like a magnetic field creating another magnetic field of opposite polarity which creates another, etc... electric fields are involved too. Radio waves in general reach much further than near-field magnetics.
Speaking of comparing Apples to oranges...
Nope - I just used other people's microwaves ;)
Have you ever actually tried it? This really doesn't work. The first time I blew up an egg in a microwave I thought of this and set a heavyish plastic jug over the egg. One minute later and the force of the explosion blew the door of the microwave open and slammed the jug against the opposite kitchen wall. Seriously, there's a lot of power in these things.
I'm British, and apart from a very few people we all use the american term, i.e. billion=10^9
Actually most of the later Russian landers survived for at least an hour, by which time their motherships which provided communication relay had gone out of range. Of course this doesn't mean they lasted days or weeks but doing that is certainly possible. Getting an actual rover to work would be much more difficult.
The one with the cool green and black cover?
Read "Eon" - a very good book involving opening "The Way"
Any chance you could post me your electric blanket? It's chilly over here and I'm not afraid of pseudoscience..
Excellent, please tell everybody about the fields at your old office so that somebody without irrational fears can enjoy the location.
Please provide some evidence that cell phones are producing or routing ionizing radiation, viz. UV and higher "through your ear and into your skull".
Alternatively provide evidence that the microwave frequencies used by cell phones are harmful in any way other than direct heating, which is negligible at these power levels.
IIRC near-field effects commonly called 'magnetic fields' drop off as the cube of the distance, but far-field effects i.e. radio waves, microwaves etc drop off as the square of the distance - explaining why radio transmissions can cover vast distances but two bar magnets won't attract past a few cm.
*cough* Occam's Razor.
FYI: "lose" is correct.
I hope we can beat relativity some day. At the moment though, it doesn't look promising.
Quake master!
Just FYI - the capsule probably leaked very very small amounts of tritium if any at all. The reason it got dimmer over 12 years is that the halflife of tritium is 12.3 years - in other words have of the atoms will have decayed in 12.3 years, so it will only be emitting half as much radiation to get turned into light. It's kind of neat to see that as something you visibly noticed!
For every man, woman and child currently alive in the world (and even that number is too big to comprehend, for me anyway), mass of moonrock equivalent to the weight of 365 Empire State Buildings would have to be removed from the moon. All that just to change its mass by 1%.
Even if that mass were coal, not H3 which stores many many times more energy, it would last us for millions of years. By which time we will have something else for an energy source.
In conclusion, unless a deliberate effort was made, there is absolutely no way we could affect the mass of the moon enough to cause a noticeable difference in tides or anything else.
P.S. Even if the mass were to change, the Moon would simply shift into a different orbit. It would not "spiral away from the Earth" or crash into us. Orbits, though complicated, are not delicate things. Yes they are in balance, but changing a factor won't just make the object fall out of the sky.
OTOH I don't see working fusion reactors turning up any day soon either.
They exist. Can't find the link now but I priced one up a couple months ago for a system and the cheapest was around $60 for a 4-port SATA card with hardware RAID 5 among others.