[Archive!] Pure mathematics, physics, chemistry, etc.: brain-training problems not related to trade in any way - page 438
You are missing trading opportunities:
- Free trading apps
- Over 8,000 signals for copying
- Economic news for exploring financial markets
Registration
Log in
You agree to website policy and terms of use
If you do not have an account, please register
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 really needs 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 on which you can stand and have a 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 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.
The formula A = sqrt( X/(2*Z) + 0.25 ) - 0.5 does not work.
So what's the answer, I see you know (if you want to take it to me)?
Done!
Yes, I got it the other way around too. But how to reverse it - to tell you the truth, I couldn't.
The formula X=2*Z*(A^2+A) has already been proved. Then we make it into a digestible form
X/2Z=A~2+A
A~2+A-X/2Z=0.
This is a quadratic equation. I think you can easily find the discriminant and through it calculate A1 and A2 - the roots of the equation.
The rock and rope problem was solved. Five, seven minutes. You want the answer?
I'll solve the wise men one. ;)
Answer to the previous problem: The Earth emits less energy than it receives from the Sun.
The rock and rope problem was solved. Five, seven minutes. You want the answer?
I'll solve the wise men one. ;)
The formula A = sqrt( X/(2*Z) + 0.25 ) - 0.5 does not work.
We take specific values.
Z=10 cm (the side of a small square cell)
А=5
I.e. the grid is the same as drawn in the condition (5 by 5 square).
What is X equal to? A total of 10 cm sections in this construction would be... uh... 5*6*2 = 60 pieces. So X = 60*10cm = 6m.
Check: 5 must equal sqrt(6/(2*0.1)+0.25) - 0.5 = sqrt(30.25)-0.5 = 5.5-0.5 It works!
2 MetaDriver: Waiting, waiting to see how you deal with the wise men...
looking forward to !!!!
OK.
Cut the rope into two pieces No. 1=25m, No. 2=50m.
One end of rope #1 is attached to the hook at the top. At the other end of rope #1, tie a loop, just enough in diameter to allow the rope to slide in.
Thread rope No. 2 through the loop to the middle. Tie the ends of rope No.2 (for insurance. optional).
Start the descent. The length of the device made of two ropes is enough to get down to the 50-metre mark, where there is the second hook and step.
Stand on the step, untie the belay knot on the rope No. 2 and pull it out of the loop at one end.
// For more safety, we tie one end of the rope to the hook first, so as not to lose our last hope... :)
Now we have a fifty-metre rope tied at fifty metres.
All that's left to do is not fall off during the descent and jump to the ground with the rope just short of the ground (consumption of knots).