[Archive!] Pure mathematics, physics, chemistry, etc.: brain-training problems not related to trade in any way - page 436

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Valera, please don't post the decision here, OK?
 
Mathemat:
Valera, please don't post the decision here, OK?

))) OK.
 
Problem! we have a cliff of 100 metres, at a height of 50 metres there is a hook, how can a climber descend a cliff with a climbing rope 75 metres long (the rope can be cut)
 
ruslanchik:
Problem! We have a cliff of 100 metres, at a height of 50 metres there is a hook, how can a climber descend a cliff with a climbing rope of 75 metres long (the rope can be cut)?

Well, you can go down without using a rope at all. Or you can jump from 25 metres.

Can the rope be tied up again after you've cut it, or can you only use pieces of it?

 

I have zero knowledge of mountaineering, so don't mind me, I won't get into this problem. So far I've had enough of the task of the wise men...

By the way, the further I look at it, the more I get into it. I can already give you examples of how the conversation ends on the first, second and third lines of the sages. I have not got to the fourth one - well, it is understandable: one still has to look for the only solution...

 

I used to solve the mountaineering problem. I used to do industrial mountaineering professionally myself. I can give you a solution right away. The rope has to be cut, but ruslanchik did not say that it is forbidden to cut it in length. That is, if you cut the rope into 2 pieces of length (making 2 pieces of 75 m each), the thickness will not be thick enough to support the weight of the climber. He also failed to mention that there is also a hook at the top of the cliff that can be used to tie the rope. There is another important factor - in the middle of the cliff at a height of 50 meters there is not only a hook, but also a small step, where you can stand and have relative freedom of movement with your hands to do something.

ValS, once you've cut the rope, you can tie up. Jump from a height of 25 metres? 1 floor is 3 meters. 25/3=8 I don't think you'll survive jumping off the eighth floor. Don't forget it's a rock, not a megalopolis - you'll get maimed, the animals will eat you. You need to get down in one piece. The rock is steep - you can't go down without a rope. And there is one more thing - a climber does not need to take off clothes in order to climb a rope - a piece of 75 meters is fully enough to be safely descended from one hundred meters high rock.

 
Mathemat:

I have zero knowledge of mountaineering, so don't mind me, I won't get into this problem. I have enough to do with the task of the wise men so far...

I declare with full responsibility that if you know the right answer, you can go down without having any mountaineering knowledge. If you are not a professional in this situation, he will invent a proper way of making knots on the spot, so that the scheme of rope use would work. So even a person who has never climbed a wall can work out a scheme. You need a scheme. Here we are neglecting the condition that the climber does not have a device for descending. I may say that getting down from the 100-metre wall "on hands" is a VERY risky business. Your hands become so weak after only 15 metres. We have to disregard physical strength and knowledge of the climber - a scheme for using a 75-meter long piece of rope is required. And what's more, the amount of rope length consumed in the knots can also be neglected.
 
drknn:

ValS, after you cut the rope, you can tie up. Jump from a height of 25 metres? 1 floor is 3 meters. 25/3=8 I don't think you'll survive jumping from 8 floors. Don't forget it's a rock, not a megalopolis - you'll get maimed and eaten by animals. You need to get down in one piece. The rock is steep - you can't go down without a rope. And there is one more thing - a climber does not need to take off clothes in order to climb a rope - a piece of 75 meters is fully enough to be safely descended from one hundred meters high rock.


I can answer you in your manner: and where in the problem is written, that it is necessary to descend alive? ) That's right.

 
drknn, I have no idea how, where or what is attached. Where are the hooks, steps, crampons and other stuff. I have no idea.
 

I take it that the expression Y=(A^2 + A) has no solution :) Is there really no formula that can calculate A? Is mathematics powerless?

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