Brain Teasers
Domo Arigato?
Situation
Situation puzzles (sometimes called lateral thinking puzzles) are ones where you need to ask lots of yes or no questions to figure out what happened in the situation. These are good puzzles for groups where one person knows the puzzle and answers the questions.Situation
On a clear December morning in Kansas, students filed into Science class ready for a good nap. Before the first student could get to sleep, the teacher, Mr. Roboto, walked in. Noticing his class seemed particularly sleepy this cold day, he decided that a nice trip outside should wake 'em up.
"Class! We are going to go on a little walk outside."
Hearing most of the class whine about the cold, he decided that he shouldn't be completely heartless.
"Ok, ok. We will still be going outside, but I guess we can have a little fire to keep us nice and warm."
This seemed to make the class a little more willing, so without further discussion, they all set out to the school's football field.
Mr. Roboto led them to midfield, where he seemed to have a little display set up. He turned to the class, and said:
"Class, I know you are all freezing, and are wondering when I'm going to start a fire. However, I seem to be in a bit of a jam. All I have is some water, wood shavings, and all ol' Mother Earth has to offer. How in the world could I make a fire?"
At this, most of the students began whining. But a few of them started yelling out ideas:
"Wait for it to start storming, and start one from the lightning!"; "Try to make super-hot steam!"; "Build a fire ray out of dirt and grass!" the students shouted out.
"All great guesses, but no. There is a much easier, faster way than all of that," Mr. Roboto replied.
After a few more minutes of wrong guesses, Mr. Roboto decided to go ahead and show them how to build the fire. It's your job to explain how it could be possible.
"Class! We are going to go on a little walk outside."
Hearing most of the class whine about the cold, he decided that he shouldn't be completely heartless.
"Ok, ok. We will still be going outside, but I guess we can have a little fire to keep us nice and warm."
This seemed to make the class a little more willing, so without further discussion, they all set out to the school's football field.
Mr. Roboto led them to midfield, where he seemed to have a little display set up. He turned to the class, and said:
"Class, I know you are all freezing, and are wondering when I'm going to start a fire. However, I seem to be in a bit of a jam. All I have is some water, wood shavings, and all ol' Mother Earth has to offer. How in the world could I make a fire?"
At this, most of the students began whining. But a few of them started yelling out ideas:
"Wait for it to start storming, and start one from the lightning!"; "Try to make super-hot steam!"; "Build a fire ray out of dirt and grass!" the students shouted out.
"All great guesses, but no. There is a much easier, faster way than all of that," Mr. Roboto replied.
After a few more minutes of wrong guesses, Mr. Roboto decided to go ahead and show them how to build the fire. It's your job to explain how it could be possible.
Answer
Mr. Roboto used a convex lens made out of ice - a form of water. This convex lens works just like a magnifying glass, it focuses the sun's rays on the wood shavings, and in a matter of minutes starts a small fire going. He just adds a few sticks lying around, and voila: he had himself a nice warm fire. The temperature plays no factor in this, he only needed sunlight, which he got on the clear day.Hide Answer Show Answer
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Comments
Kinda hard, because you didn't know that the water was ice and in a convex shape, but it was fun.
i read this one somewhere before..... so it was pretty easy, good teaser tho
Well written and overall a good teaser...but I saw a "Myth Busters" episode that showed how difficult to impossible it was to A) freeze the water until it was clear enough to properly focus the light B) shape the ice so that the focal point was precise enough to work and of course C) start the fire before the ice lens started melting on the wood! But that's just food for thought
interesting
Yeah, I agree with kistin14...
Perhaps if it was mentioned that the water was frozen, it might have been a bit more solvable. I agree with BunnyCups, it would be very hard to do.
I liked this one a lot SWAFF!
don't make it so long
Great teaser.
i just thought the water was in a glass jar... that solves the problem of it not working (i saw that episode of mythbusters too)
I'm not understanding if the water was already convex-shaped ice. If it wasn't though, then the weather would come into play because you would have to freeze the water.
My comment: DUH, ice is a form of water!
I thought he used a pair of glasses!
Clever Swaff , but I don't think anyone would be very happy with a fire on the football field, and just out of curiosity why did you pick Domo Arigato (Japanese for thank you ) for the title?
Just because the teacher's name is Mr. Roboto...
Basically, I couldn't think of a better title.
Basically, I couldn't think of a better title.
This theory was recently proven to be highly unlikely if not impossible, the prescision needed to create a convex lens capable to focussing light into a single point able to ignite a flame would be almost impossible to achieve through the freezing of water.
Not true -- this is totally possible. They did it on MythBusters, successfully. One poster above said that they had trouble with the ice lens, but on the show they pointed out that their big problem was that the lens was melting -- something that wouldn't be a problem on a cold day.
On the other hand, it is tricky to get ice to freeze clear. Usually it is cloudy from the air that is dissolved in the water. They discussed this on MythBusters, too.
On the other hand, it is tricky to get ice to freeze clear. Usually it is cloudy from the air that is dissolved in the water. They discussed this on MythBusters, too.
belongs under science
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