Puzzles
That it does. Your turn, Nyamaza.
"I don't know why, but watching 12-year old Japanese girls flinging their school uniforms at each other was wildly entertaining." - Azrael, Japanese Exchange Teacher.
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Cyril_Dran
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We appear to be on a matrix logic streak.. I'm sorry for not contributing, but I lost my taste for them long ago when someone had a 6 element, 24 clue matrix logic. I DID solve it, but it took me most of a month...
In other news, a lateral thinking puzzle I like, if Nyamaza doesn't mind me posting here.. It's not really a riddle or a puzzle, but it fits here. The puzzle is interactive, and you are allowed to ask the person telling the puzzle any yes or no question, but the answer will require some imagination; there's not necessarily a logical conclusion to the puzzle that can be derived from clues in the description. So, lets give it a shot.
A woman has stolen 2 5 pound balls of solid gold and weighs 83 pounds. She is fleeing pursuers and comes to a bridge that can only support 90 pounds. She can not throw the balls across the bridge, and does not have time to take one and come back. How does she get across?
A more simple one: A man walks into a bar and is immediately knocked unconscious. Why?
In other news, a lateral thinking puzzle I like, if Nyamaza doesn't mind me posting here.. It's not really a riddle or a puzzle, but it fits here. The puzzle is interactive, and you are allowed to ask the person telling the puzzle any yes or no question, but the answer will require some imagination; there's not necessarily a logical conclusion to the puzzle that can be derived from clues in the description. So, lets give it a shot.
A woman has stolen 2 5 pound balls of solid gold and weighs 83 pounds. She is fleeing pursuers and comes to a bridge that can only support 90 pounds. She can not throw the balls across the bridge, and does not have time to take one and come back. How does she get across?
A more simple one: A man walks into a bar and is immediately knocked unconscious. Why?
All fear the RP character from the completely private RP ^_^.
Current psuedonym/RP character count: 25
-Adding a touch of sanity, or insanity, where needed to balance the flow. .... Nah, I just like playing devil's advocate ^_^
Current psuedonym/RP character count: 25
-Adding a touch of sanity, or insanity, where needed to balance the flow. .... Nah, I just like playing devil's advocate ^_^
You'd probably be knocked out too if you slammed your head into a bar. :)
As to the other one...
1) leave one of the balls behind, and be happy with what she gets.
2) strip naked and lose 3 pounds of clothing, bringing her under 80lbs.
3) swim.
4) hide the loot and come back later. (could be as fast as throwing them in the bushes)
5) the question is a trick one, and the 83lbs includes the gold.
6) find another route.
7) cross the bridge very quickly and hope it doesn't crunch.
8) roll the balls across the bridge. (balls being advantageous over bars here)
9) unravel some item of clothing, tie it to one of the balls, run across, then pull the remaining one over.
10) if the bridge is very close to the river level, cross while holding the balls and her arms underwater, reducing the weight put upon the bridge. (having just the balls but not her arms underwater would not reduce it enough, as gold is very dense compared to water)
11) walk very slowly. if we assume the 90 pound limit is a normal walking gait, with significant acceleration/deceleration with steps, walking slower would allow a higher weight limit.
I'd list more, but I'm tired, and need sleep. :)
--Randy
As to the other one...
1) leave one of the balls behind, and be happy with what she gets.
2) strip naked and lose 3 pounds of clothing, bringing her under 80lbs.
3) swim.
4) hide the loot and come back later. (could be as fast as throwing them in the bushes)
5) the question is a trick one, and the 83lbs includes the gold.
6) find another route.
7) cross the bridge very quickly and hope it doesn't crunch.
8) roll the balls across the bridge. (balls being advantageous over bars here)
9) unravel some item of clothing, tie it to one of the balls, run across, then pull the remaining one over.
10) if the bridge is very close to the river level, cross while holding the balls and her arms underwater, reducing the weight put upon the bridge. (having just the balls but not her arms underwater would not reduce it enough, as gold is very dense compared to water)
11) walk very slowly. if we assume the 90 pound limit is a normal walking gait, with significant acceleration/deceleration with steps, walking slower would allow a higher weight limit.
I'd list more, but I'm tired, and need sleep. :)
--Randy
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Alfador
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Argh. I'd thought of 1) and 8) above there...
An alternative, gold being soft, she could poke finger holes into one of the balls and bowl it across. That, however, is merely an improvement on 8). An advantage to 1), however, is that the pursuers will likely be slightly distracted with securing the gold ball that was left behind.
An alternative, gold being soft, she could poke finger holes into one of the balls and bowl it across. That, however, is merely an improvement on 8). An advantage to 1), however, is that the pursuers will likely be slightly distracted with securing the gold ball that was left behind.
Get across what? She comes to the bridge, but there is no statement that she must cross it. What if she just needs to get across the forest by the bridge. Then there's the matter of the bridge and what it bridges. A dry gulli is not difficult to cross, bridge or no bridge. For that matter, what type of bridge? A pool bridge? A nose bridge?
I think Randy summed up the best scenarios for a straightforward "must get across bridge over impassable terrain" scenario.
Poke holes in the gold? *hides balls to prevent Alfy from poking them*
I think Randy summed up the best scenarios for a straightforward "must get across bridge over impassable terrain" scenario.
Poke holes in the gold? *hides balls to prevent Alfy from poking them*
"I don't know why, but watching 12-year old Japanese girls flinging their school uniforms at each other was wildly entertaining." - Azrael, Japanese Exchange Teacher.
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Cyril_Dran
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Nyamaza got it right, at least the intended answer. Something I forgot to mention in the problem: The bridge was over a chasm. Also, for the spirit of the problem, she had to get both balls across the bridge at once, and she had to do it of her own free power.. the weight of her clothing in the problem is negligible. The bridge was pretty long, hence why she couldn't roll or lob them across. Even at a stand still, her dead weight would have broken the bridge with both balls; the weight limit was very strict.
As for the bar problem, got it in one. Good job.
Um, I think I can remember a few more of them if you guys want me to.. I used to have a book of the things, but I got rid of it a while back...
As for the bar problem, got it in one. Good job.
Um, I think I can remember a few more of them if you guys want me to.. I used to have a book of the things, but I got rid of it a while back...
All fear the RP character from the completely private RP ^_^.
Current psuedonym/RP character count: 25
-Adding a touch of sanity, or insanity, where needed to balance the flow. .... Nah, I just like playing devil's advocate ^_^
Current psuedonym/RP character count: 25
-Adding a touch of sanity, or insanity, where needed to balance the flow. .... Nah, I just like playing devil's advocate ^_^
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Allan_ecker
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Of course, she'd better be one HELL of a juggler to never accelerate any ball with more than -little more- than its own weight, which she'd have to in order to still make it.
<A HREF="http://umlauthouse.comicgenesis.com" TARGET=_blank>UH2: The Mayhem of a New Generation</A>
"Death and taxes are unsolved engineering problems."
--Romano Machado
"Death and taxes are unsolved engineering problems."
--Romano Machado
Umm. I would be willing to bet the juggling one can be proved not to work, and wouldn't be nearly as successful as walking slower.
A simple proof by contradiction would be that if juggling the balls reduced the average downward force, assuming gravity did not change, mass must have been destroyed.
Another proof that the impulse load would be higher than the limit could be done by realizing that she will have to throw each ball in less or equal time than it takes the other one to complete its trajectory and be caught by her again. If we assume she applies the absolute lowest force possible, and applies it perfectly evenly throughout her catching and throwing each ball, she still must apply at least twice the weight of the ball in force to lift it up again. If she does not apply at least 2gs of force, the ball will not attain enough velocity to make its arc through the air before the other one lands, as once it leaves her hand, it has 1g of downward force on it, so she has to apply a net 1g of upward acceleration (assuming, again, the absolute minimum force she can apply, clearly she could apply more) to get it back in the air for the same length of time. Thus, perfectly jugling two balls with a perfect 50% ball duty cycle and a perfect constant force, is equivelent to carrying two balls without moving them. (ok, so I suck at explaining things)
So, no, I don't think juggling is a valid answer.
Hide in the bushes, wait for the guards to assume you crossed the bridge, let the bridge break with them on it, and happily stroll along to the next bridge? :)
--Randy
A simple proof by contradiction would be that if juggling the balls reduced the average downward force, assuming gravity did not change, mass must have been destroyed.
Another proof that the impulse load would be higher than the limit could be done by realizing that she will have to throw each ball in less or equal time than it takes the other one to complete its trajectory and be caught by her again. If we assume she applies the absolute lowest force possible, and applies it perfectly evenly throughout her catching and throwing each ball, she still must apply at least twice the weight of the ball in force to lift it up again. If she does not apply at least 2gs of force, the ball will not attain enough velocity to make its arc through the air before the other one lands, as once it leaves her hand, it has 1g of downward force on it, so she has to apply a net 1g of upward acceleration (assuming, again, the absolute minimum force she can apply, clearly she could apply more) to get it back in the air for the same length of time. Thus, perfectly jugling two balls with a perfect 50% ball duty cycle and a perfect constant force, is equivelent to carrying two balls without moving them. (ok, so I suck at explaining things)
So, no, I don't think juggling is a valid answer.
Hide in the bushes, wait for the guards to assume you crossed the bridge, let the bridge break with them on it, and happily stroll along to the next bridge? :)
--Randy
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Allan_ecker
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...
Yeah, he's totally right.
Yeah, he's totally right.
<A HREF="http://umlauthouse.comicgenesis.com" TARGET=_blank>UH2: The Mayhem of a New Generation</A>
"Death and taxes are unsolved engineering problems."
--Romano Machado
"Death and taxes are unsolved engineering problems."
--Romano Machado
It's the joke about the trucker that keeps on stopping his truck on a long suspension bridge so he can run out and bang on the sides of his trailer. His 4000 lbs. load of chickens puts him 2000 lbs. over the bridge's load limit so he's gotta' keep half his load flapping/flying. We all know this is too absurd to work, which is why the joke is funny.
Kudos to Randy for knowing his stuff ('cause I sure didn't).
Kudos to Randy for knowing his stuff ('cause I sure didn't).
"I don't know why, but watching 12-year old Japanese girls flinging their school uniforms at each other was wildly entertaining." - Azrael, Japanese Exchange Teacher.
Well, if we assume chickens can fly (....), and assume it's an open truck (i.e. a cage) rather than an enclosed one, that could work. Possibly. Maybe.
If the truck is closed, all the flying/flapping/etc is internal forces, with the reaction pushing down on the truck due to the increase in air pressure in the sealed environment.
But if it's open, it's theoretically possible the chickens' forces are applied to the rest of the world instead of to the truck, by allowing any air pressure changes to equalize with the outside environment, intead of acting on the truck bed.
A bird with better flight properties would be a better example, though.
In any case, that one is a lot more reasonable than the ball-grabbing woman. :)
--Randy
If the truck is closed, all the flying/flapping/etc is internal forces, with the reaction pushing down on the truck due to the increase in air pressure in the sealed environment.
But if it's open, it's theoretically possible the chickens' forces are applied to the rest of the world instead of to the truck, by allowing any air pressure changes to equalize with the outside environment, intead of acting on the truck bed.
A bird with better flight properties would be a better example, though.
In any case, that one is a lot more reasonable than the ball-grabbing woman. :)
--Randy
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Cyril_Dran
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The original wording of the puzzle had bigger tolerances for the weight, but it's impractical/improbable that she'd be able to juggle 15 pound balls of gold.
A non physics based one:
A hunter wakes up at his camp and begins looking for a bear. He goes roughly one mile south and spots a bear. He then follows it one mile east, where he shoots and kills it. He then moves one mile north, and arrives back at camp.
How is this possible?
If you can't just guess it, feel free to ask questions. It's part of the joke. I also have a more specific, yet obscure hint, that I will PM to those who want it.
A non physics based one:
A hunter wakes up at his camp and begins looking for a bear. He goes roughly one mile south and spots a bear. He then follows it one mile east, where he shoots and kills it. He then moves one mile north, and arrives back at camp.
How is this possible?
If you can't just guess it, feel free to ask questions. It's part of the joke. I also have a more specific, yet obscure hint, that I will PM to those who want it.
All fear the RP character from the completely private RP ^_^.
Current psuedonym/RP character count: 25
-Adding a touch of sanity, or insanity, where needed to balance the flow. .... Nah, I just like playing devil's advocate ^_^
Current psuedonym/RP character count: 25
-Adding a touch of sanity, or insanity, where needed to balance the flow. .... Nah, I just like playing devil's advocate ^_^
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Allan_ecker
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North Pole, dude.
Also, it doesn't matter how great the tolerances are. If she can't do it carrying them, she can't do it juggling. End of story.
Also, it doesn't matter how great the tolerances are. If she can't do it carrying them, she can't do it juggling. End of story.
<A HREF="http://umlauthouse.comicgenesis.com" TARGET=_blank>UH2: The Mayhem of a New Generation</A>
"Death and taxes are unsolved engineering problems."
--Romano Machado
"Death and taxes are unsolved engineering problems."
--Romano Machado
New riddle. Tired of physics and matrices are we? Let's try something old... and I hope I haven't done this one before.
O T T F F S S E N T What is the next letter and why?
O T T F F S S E N T What is the next letter and why?
"I don't know why, but watching 12-year old Japanese girls flinging their school uniforms at each other was wildly entertaining." - Azrael, Japanese Exchange Teacher.
Well done! Same dealie for this one, too:
A E F H I K L M N...
A E F H I K L M N...
"I don't know why, but watching 12-year old Japanese girls flinging their school uniforms at each other was wildly entertaining." - Azrael, Japanese Exchange Teacher.
No it should not; "J" is rejected from the line-up I gave.
"I don't know why, but watching 12-year old Japanese girls flinging their school uniforms at each other was wildly entertaining." - Azrael, Japanese Exchange Teacher.