[Archive!] Pure mathematics, physics, chemistry, etc.: brain-training problems not related to trade in any way - page 246

[михаил потапыч]

Mathemat >>:

Это при условии, что они отражаются от стенок под тем же углом.

Naturally

[Sceptic Philozoff]

So how do they recognise it - or do they have a stopwatch?

So, let's assume they're not blind but just moving in complete darkness. How will they draw the midpoint perpendiculars to the chords to calculate the centre?

[михаил потапыч]

MaStak >>:

Даг касание и есть цель, центр потом уже не нужен

Touching a circle

Provided they know initially that they are in a circle

[EvGen]

Mathemat >>:

И как же они его узнают - или у них есть секундомер?

Well, it's a room, a big round room.

[михаил потапыч]

Mathemat >>:

И как же они его узнают - или у них есть секундомер?

After the first touch we get a line through the centre

after the second touch, the second

intersection - centre

[Sceptic Philozoff]

If they remember all the points they have been to and know how to construct perpendiculars to chords, they will meet quickly.

[EvGen]

So, the beginning

In a large (D=20m) circular room there are 2 blind people.

[Sceptic Philozoff]

...possessing the memory of the points visited and with baalal compasses and rulers.

[михаил потапыч]

Mathemat >>:

Если они помнят все точки, в которых побывали, и умеют строить перпендикуляры к хордам, то они встретятся быстро.

Well, yeah.

There are no conditions at all

[Sceptic Philozoff]

It's a bit of a wild card. Someone will come in here and wonder what we are doing.