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        riddles >> what happened >> Hourglass
        
(Message started by: alien on Apr 24^th, 2005, 9:15am)

Title: Hourglass
Post by alien on Apr 24^th, 2005, 9:15am

John and Mark, friends from the Always Coca-Cola riddle, are chatting at Mark's. John is thirsty but Mark has nothing except milk in his refrigerator, so he brings him a glass of milk. John asks Mark to borrow him $3000 again. Mark says: "If you can tell me how one can make a small hourglass that has milk instead of sand and where it takes more than 5 minutes for milk to pass from one bulb to the other, I will lend you the money". John comes up with the solution again, and Mark lends him the money. What was his solution?

Title: Re: Hourglass
Post by Grimbal on Apr 27^th, 2005, 8:53am

[hide] freeze and grind the milk ? [/hide]

Title: Re: Hourglass
Post by alien on Apr 28^th, 2005, 2:30am

[hide]You do freeze the milk, but there is really no need to grind it: just put the hourglass in the freezer and then take it out on the room temperature when milk in the bulb freezes.[/hide]

Title: Re: Hourglass
Post by towr on Apr 28^th, 2005, 3:03am

But then it won't run. In fact unless you do it grimbals way, it is most unlikely to run. In which case it isn't really an hour glass.

Title: Re: Hourglass
Post by BNC on Apr 28^th, 2005, 3:21am

It should "run" once the milk melts...

Title: Re: Hourglass
Post by alien on Apr 28^th, 2005, 4:03am

BNC is correct. Frozen milk will melt and slowly pass to the other bulb.

Of course, a hourglass that has milk instead of sand sucks and anybody who makes it is either crazy or testing the solution for this riddle. All in all, I could've said something like two joined bulbs with a narrow passage between them but instead of such description I just said hourglass. ;)

Title: Re: Hourglass
Post by towr on Apr 28^th, 2005, 4:07am

No, because the air will be trapped, and can't get past the milk. No better than it could with water. The hole connecting the two bulbs is too small. With a grainy material the air can escape to the top bulb between the grains, but with liquids that won't work. You'll either need a much bigger hole (which doesn't provide reliable timing), or two openings at different heights (but that deviates much more from a standard hour glass).

Title: Re: Hourglass
Post by alien on Apr 28^th, 2005, 4:35am

Check out the big brain on towr! :o

Title: Re: Hourglass
Post by towr on Apr 28^th, 2005, 4:54am

something like this (http://www.garrettspecialties.com/html/acrylicsand.html) might work

Title: Re: Hourglass
Post by BNC on Apr 28^th, 2005, 8:48am

I'm not so sure it wouldn't work... at least for a while.
Since the milk freeze while on the bottom of the bottom part, when turned over, it will be on the top of the top part. Hence, it will drip down. Won't a single drop fall to the bottom?

Title: Re: Hourglass
Post by towr on Apr 28^th, 2005, 10:06am

I'm pretty sure in most cases a single drop will already clog the hole. Also because both bulbs are isolated from the rest of the world, air can't go out through any other way than through the connection to the other bulb.

Title: Re: Hourglass
Post by ankur on Jun 10^th, 2005, 12:03pm

What iff there is vaccum in the hour glass - in that case i guess the milk drops will collect on the lower bulb.

???

Title: Re: Hourglass
Post by Larissa_Preedy on Jun 11^th, 2005, 10:03am

can't you just alot of milk, with a small hole, so it takes sooo long to get through?

sorry, i'm tired :-[

Title: Re: Hourglass
Post by towr on Jun 12^th, 2005, 8:58am

on 06/10/05 at 12:03:05, ankur wrote:

What iff there is vaccum in the hour glass - in that case i guess the milk drops will collect on the lower bulb.

Ignoring evaporation (which makes a good vacuum impossible) that's a very good observation. I should have thought of that :P

Title: Re: Hourglass
Post by Speaker on Jun 13^th, 2005, 1:25am

Well, towr, I agree with what you are saying, but...my deux sense.

You do not need to freeze the milk. Just use the powdered milk that is used for the baby's bottle.

You could freeze a small quantity of milk in the top half of the hour glass. Then take it out of the freezer and turn it over. Now, it will take a certain amount of time (5 minutes right) for the milk to melt and run down the sides of the hour glass. (It does not go through the tiny hole. The time measured is just the time to melt the milk.)

You could put a small amount of milk in the bottom half, then heat the milk. The vapor then rises to the top. When the bottom half is dry (but before it breaks from the heat) five minutes have passed. (This might be impossible, but that never stopped me from putting something forth as an answer. It is similar to small coffer percolators.)

Title: Re: Hourglass
Post by towr on Jun 13^th, 2005, 2:25am

on 06/13/05 at 01:25:29, Speaker wrote:

You do not need to freeze the milk. Just use the powdered milk that is used for the baby's bottle.

Isn't powdered milk freeze-dried? So it still needs to have been frozen ;D

Title: Re: Hourglass
Post by Speaker on Jun 13^th, 2005, 9:40pm

Is it freeze dried???? I think it is lyophilized. But, that depends on who supplies your baby formula. Me, all my powdered milk comes from Peruvian Llamas. ;)