A 16" gun is not going to reliably hit a one-meter target, and battleship guns were deliberately mounted inaccurate to create a salvo pattern to maximize the chances of a hit per salvo. A battleship is an awfully expensive way to fire one-ton shells up to 20 miles away with limited accuracy. It's great for firing at large armored naval targets, which are currently in short supply.
Do you realize how many people have been saying things like that since before WWI (i.e., over a century now)? I see no reason to believe it's true now.
Back in the Vietnam War, one of my favorite humor columnists (Art Buchwald) compared what we were spending on the war, number of enemy dead, and what the Mafia was charging at that time for a contract murder. The Mafia was cheaper.
The 16" guns fired 2700-pound armor-piercing shells. The HE shells were lighter, I believe about 2K, and the Navy later developed shells with less steel and more explosives.
Pearl Harbor was not invaded. It was hit, once, on a very long-range carrier mission. The Japanese developed means of refueling at sea just for that one mission. They did make a very few attacks on the mainland US, including (IIRC two) submarine bombardments that accomplished nothing, and sending incendiary balloon bombs in 1945 that killed a few civilians in one incident.
Some Aleutian islands were indeed invaded, but Alaska was not a state then.
The longest US ranges in WWII were a little over 35,000 yards, or call it 18 nautical miles or about 20 statute miles. The guns could fire further, but their elevation was limited by the turrets. The Japanese battleships could fire significantly farther, although it's not clear to me that firing at extreme range with a minute and a half shell flight time is going to be worth it. The farthest a WWII battleship fired and actually hit something was something like 25,000 yards.
Naval shells have historically not been lead. In the Twentieth Century, they were made of steel. Big balls of lead are indeed useless, which is why cannonballs were last serious weapons of war in the Nineteenth Century.
If you're shooting, course changes mess up your own fire control, since the precise movement of the ship is hard to model. In WWII, such maneuvers would be used by ships that were not currently shooting but wanted to close the range.
The only ship armor in WWII that could stop an armor-piercing shell from the latest US 16" guns was 24" of armor plate (not face-hardened) at a 45-degree angle from vertical, found on the front of the turrets of the Japanese battleships Yamato and Musashi. Putting that two feet of armor plate vertical would have allowed penetration at short range. 18" of reinforced concrete would just slow one of those shells down some, although it would probably stop the large lead cannonballs you seem to imagine were used.
Typically, the point of naval gunfire is to throw a lot of shells into an area, since there's better ways to pick out individual targets if you can identify them. However, if these things throw a lot of shells, they'll wind up exceeding the defense budget, so I really don't know what they're good for.
Actually, that five miles you cite was fairly close range, and the sophisticated fire control systems of the more advanced WWII navies would consistently get hits at that range. The guns were typically fired so the shells would land in a large pattern, to increase the odds of hitting first at the cost of total number of hits, since the time of flight was significant and ships can move.
To run the EM perpetual motion machine, you need to provide electricity. However, since the circle is turning, you can use that kinetic energy to produce electricity. As long as energy is conserved, what you've got there is indeed a complicated flywheel, except with lots more ways to lose energy.
Therefore, it's a perpetual motion machine if and only if the EM drive can produce significantly more energy than it takes in. If it does, we can package the generator and the EM wheel as a unit, provide enough electricity to get it going fast enough, and then turn off the power going in and use the excess power going out as we please. That's what you appear to mean by perpetual motion machine.
The reason why the EM drive, as described, can produce arbitrarily more kinetic energy than it takes in in electrical energy has been discussed already in this thread.
Mechanical and electrical losses have nothing to do with perpetual motion machines, as normally defined. If you have no friction or other forces, you can put something into motion and it will stay in motion indefinitely. That is not what is normally meant by a perpetual motion machine, if for no other reason that we can't make machines with no friction or other sources of energy loss (if it's producing heat, it's making energy.)
The definition being used by other people in this thread is something that puts out more energy than it takes in. I'm happy to drop all mention of perpetual motion machines if we can come up with another phrase for it. Energy source?
Assume we put these EM drives around a circle and turn them on. They will turn the wheel, and we can get electricity out of this rotation which we can use to power the drives and turn the wheel. If energy is conserved, then with any apparatus we can construct this is going to run down really fast. However, we're talking about something that will take in energy and produce momentum without any other changes. Energy works out to momentum times speed, meaning that a momentum increase will take more energy if starting at 40mph than at 20mph.
However, the claim is that we have energy in and change of momentum out, and, if relativity holds the energy to momentum ratio has to be constant no matter what the speed. Therefore, we can make the EM drive go sufficiently fast that it's taking electrical energy in and producing more kinetic energy than it takes in, by any desired margin. We can therefore have EM drives spinning a wheel that produces more than enough energy to power the EM drives and mechanical and electrical inefficiencies.
You are reasoning according to the laws of physics as we know them, which is generally good, but you're not taking into account that the EM drive violates conservation of energy and momentum, and therefore violates the laws of physics we know.
My company is not a soul-sucking demon. It's a really good place to work. Of course, senior management has been going through a lot of changes, so while I think they'll keep the company culture intact I'm not as confident as I was with the old management.
The British Empire needed flexible thinkers. They didn't have to be Indian, and encouraging Indians in general to be flexible thinkers was not considered the right thing to do.
There wasn't a single bullet fired in WW2 on the continent of South America,
Peru and Ecuador fought a war in 1941-1942. I'm not exactly sure, but the first New World country to use paratroops in battle might be Peru. The US was sufficiently distracted that it didn't react to Peruvian bombing of US-owned plantations.
Given the superiority of the Peruvian army and air force, pretty much nothing outside Ecuador got destroyed.
The advertising program that says a man needs to put a few months' pay into buying a diamond for an engagement ring reminds me of Goebbels campaign to make Mein Kampf a standard wedding present for young couples. He made Hitler rich on the royalties.
We currently can't travel at a significant fraction of the speed of light, but look up the 1960s Project Orion. That was a plan for a spaceship to fire off nuclear bombs for propulsion. It was expected to reach a significant fraction of C. Modern physics says we aren't gong faster than light, not that we aren't going to achieve a speed that can manage interstellar travel.
We can also have generation ships, or possibly automatic ships with crews in some sort of stasis or being frozen. The laws of physics don''t say that either of those ideas is impossible. We're nowhere near ready for the engineering challenges, but that might well change over the next millennium or so.
There's other possibilities. The Alcubierre drive might well work, if we can find enough stuff with negative mass and find a sufficiently powerful power plant. It's certain that modern physics is wrong about some things, and it's possible that there's something that would make interstellar travel relatively easy.
The reason he said that was not that he was afraid of Clinton, but that people who did what she did with classified material have not historically been prosecuted.
And I want you to find another human on the planet who was negligent with US classified information and was criminally prosecuted. After looking at several cases, I found one who agreed to plead guilty to a misdemeanor charge but in the end didn't have to. Some of them had their security clearance revoked temporarily or permanently. Comey was correct when he said that there was no precedent for criminal prosecution for negligence.
It's far, far more likely to be experimental error than a violation of physics as we know it. That particular belief system you're talking about is the laws of physics as we know it and as we've painstakingly experimented with for centuries. Claiming that momentum isn't conserved under mundane circumstances (like bouncing microwaves around) is a truly extraordinary claim, and we don't have truly extraordinary experimental results.
If we ran the thing for a long time in space, we'd eliminate some possible sources of experimental error and it would be easier to figure out what went on. (My guess is that it wouldn't work in space.)
Short version - a perpetual motion machine can take in energy. It has to return more energy than it gets. Assuming this thing works as advertised, it's possible to put a finite amount of energy into it and get an infinite* amount of energy out. Therefore, you prime the perpetual motion machine generator to get it started and then use that power to run the main drive.
an engine isn't much use if you can't control whether it sends you forward or backward.
Reminds me of the Daffy Duck cartoon "Duck Dodgers of the Twenty Four And A Half Century!" Duck Dodgers gets into his rocket ship, the rockets fire, and the ship shrinks back into the launch pad. At least until he takes it out of reverse.
Slashdot Mirror
A 16" gun is not going to reliably hit a one-meter target, and battleship guns were deliberately mounted inaccurate to create a salvo pattern to maximize the chances of a hit per salvo. A battleship is an awfully expensive way to fire one-ton shells up to 20 miles away with limited accuracy. It's great for firing at large armored naval targets, which are currently in short supply.
Do you realize how many people have been saying things like that since before WWI (i.e., over a century now)? I see no reason to believe it's true now.
Back in the Vietnam War, one of my favorite humor columnists (Art Buchwald) compared what we were spending on the war, number of enemy dead, and what the Mafia was charging at that time for a contract murder. The Mafia was cheaper.
I love being pedantic on Slashdot, so here goes:
The 16" guns fired 2700-pound armor-piercing shells. The HE shells were lighter, I believe about 2K, and the Navy later developed shells with less steel and more explosives.
Pearl Harbor was not invaded. It was hit, once, on a very long-range carrier mission. The Japanese developed means of refueling at sea just for that one mission. They did make a very few attacks on the mainland US, including (IIRC two) submarine bombardments that accomplished nothing, and sending incendiary balloon bombs in 1945 that killed a few civilians in one incident.
Some Aleutian islands were indeed invaded, but Alaska was not a state then.
The longest US ranges in WWII were a little over 35,000 yards, or call it 18 nautical miles or about 20 statute miles. The guns could fire further, but their elevation was limited by the turrets. The Japanese battleships could fire significantly farther, although it's not clear to me that firing at extreme range with a minute and a half shell flight time is going to be worth it. The farthest a WWII battleship fired and actually hit something was something like 25,000 yards.
Under the circumstances, wouldn't leveling a small town require a special Congressional appropriations bill?
Naval shells have historically not been lead. In the Twentieth Century, they were made of steel. Big balls of lead are indeed useless, which is why cannonballs were last serious weapons of war in the Nineteenth Century.
If you're shooting, course changes mess up your own fire control, since the precise movement of the ship is hard to model. In WWII, such maneuvers would be used by ships that were not currently shooting but wanted to close the range.
The only ship armor in WWII that could stop an armor-piercing shell from the latest US 16" guns was 24" of armor plate (not face-hardened) at a 45-degree angle from vertical, found on the front of the turrets of the Japanese battleships Yamato and Musashi. Putting that two feet of armor plate vertical would have allowed penetration at short range. 18" of reinforced concrete would just slow one of those shells down some, although it would probably stop the large lead cannonballs you seem to imagine were used.
Typically, the point of naval gunfire is to throw a lot of shells into an area, since there's better ways to pick out individual targets if you can identify them. However, if these things throw a lot of shells, they'll wind up exceeding the defense budget, so I really don't know what they're good for.
Actually, that five miles you cite was fairly close range, and the sophisticated fire control systems of the more advanced WWII navies would consistently get hits at that range. The guns were typically fired so the shells would land in a large pattern, to increase the odds of hitting first at the cost of total number of hits, since the time of flight was significant and ships can move.
To run the EM perpetual motion machine, you need to provide electricity. However, since the circle is turning, you can use that kinetic energy to produce electricity. As long as energy is conserved, what you've got there is indeed a complicated flywheel, except with lots more ways to lose energy.
Therefore, it's a perpetual motion machine if and only if the EM drive can produce significantly more energy than it takes in. If it does, we can package the generator and the EM wheel as a unit, provide enough electricity to get it going fast enough, and then turn off the power going in and use the excess power going out as we please. That's what you appear to mean by perpetual motion machine.
The reason why the EM drive, as described, can produce arbitrarily more kinetic energy than it takes in in electrical energy has been discussed already in this thread.
Mechanical and electrical losses have nothing to do with perpetual motion machines, as normally defined. If you have no friction or other forces, you can put something into motion and it will stay in motion indefinitely. That is not what is normally meant by a perpetual motion machine, if for no other reason that we can't make machines with no friction or other sources of energy loss (if it's producing heat, it's making energy.)
The definition being used by other people in this thread is something that puts out more energy than it takes in. I'm happy to drop all mention of perpetual motion machines if we can come up with another phrase for it. Energy source?
Assume we put these EM drives around a circle and turn them on. They will turn the wheel, and we can get electricity out of this rotation which we can use to power the drives and turn the wheel. If energy is conserved, then with any apparatus we can construct this is going to run down really fast. However, we're talking about something that will take in energy and produce momentum without any other changes. Energy works out to momentum times speed, meaning that a momentum increase will take more energy if starting at 40mph than at 20mph.
However, the claim is that we have energy in and change of momentum out, and, if relativity holds the energy to momentum ratio has to be constant no matter what the speed. Therefore, we can make the EM drive go sufficiently fast that it's taking electrical energy in and producing more kinetic energy than it takes in, by any desired margin. We can therefore have EM drives spinning a wheel that produces more than enough energy to power the EM drives and mechanical and electrical inefficiencies.
You are reasoning according to the laws of physics as we know them, which is generally good, but you're not taking into account that the EM drive violates conservation of energy and momentum, and therefore violates the laws of physics we know.
My company is not a soul-sucking demon. It's a really good place to work. Of course, senior management has been going through a lot of changes, so while I think they'll keep the company culture intact I'm not as confident as I was with the old management.
The British Empire needed flexible thinkers. They didn't have to be Indian, and encouraging Indians in general to be flexible thinkers was not considered the right thing to do.
Peru and Ecuador fought a war in 1941-1942. I'm not exactly sure, but the first New World country to use paratroops in battle might be Peru. The US was sufficiently distracted that it didn't react to Peruvian bombing of US-owned plantations.
Given the superiority of the Peruvian army and air force, pretty much nothing outside Ecuador got destroyed.
The advertising program that says a man needs to put a few months' pay into buying a diamond for an engagement ring reminds me of Goebbels campaign to make Mein Kampf a standard wedding present for young couples. He made Hitler rich on the royalties.
We currently can't travel at a significant fraction of the speed of light, but look up the 1960s Project Orion. That was a plan for a spaceship to fire off nuclear bombs for propulsion. It was expected to reach a significant fraction of C. Modern physics says we aren't gong faster than light, not that we aren't going to achieve a speed that can manage interstellar travel.
We can also have generation ships, or possibly automatic ships with crews in some sort of stasis or being frozen. The laws of physics don''t say that either of those ideas is impossible. We're nowhere near ready for the engineering challenges, but that might well change over the next millennium or so.
There's other possibilities. The Alcubierre drive might well work, if we can find enough stuff with negative mass and find a sufficiently powerful power plant. It's certain that modern physics is wrong about some things, and it's possible that there's something that would make interstellar travel relatively easy.
She's getting off because anyone who did what she did would have. Negligence with classified material is not criminally prosecuted.
The reason he said that was not that he was afraid of Clinton, but that people who did what she did with classified material have not historically been prosecuted.
And I want you to find another human on the planet who was negligent with US classified information and was criminally prosecuted. After looking at several cases, I found one who agreed to plead guilty to a misdemeanor charge but in the end didn't have to. Some of them had their security clearance revoked temporarily or permanently. Comey was correct when he said that there was no precedent for criminal prosecution for negligence.
It's far, far more likely to be experimental error than a violation of physics as we know it. That particular belief system you're talking about is the laws of physics as we know it and as we've painstakingly experimented with for centuries. Claiming that momentum isn't conserved under mundane circumstances (like bouncing microwaves around) is a truly extraordinary claim, and we don't have truly extraordinary experimental results.
And it's much more likely to be an experimental error or a misunderstanding.
If we ran the thing for a long time in space, we'd eliminate some possible sources of experimental error and it would be easier to figure out what went on. (My guess is that it wouldn't work in space.)
Short version - a perpetual motion machine can take in energy. It has to return more energy than it gets. Assuming this thing works as advertised, it's possible to put a finite amount of energy into it and get an infinite* amount of energy out. Therefore, you prime the perpetual motion machine generator to get it started and then use that power to run the main drive.
Reminds me of the Daffy Duck cartoon "Duck Dodgers of the Twenty Four And A Half Century!" Duck Dodgers gets into his rocket ship, the rockets fire, and the ship shrinks back into the launch pad. At least until he takes it out of reverse.