All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Science
Cool it fast... (Posted on 2003-04-01) Difficulty: 3 of 5
A blacksmith wishes to cool his hot piece of steel as rapidly as possible. He has a bucket of ice-water and a bucket of oil (at room temperature). Which bucket should he dump his steel into?

See The Solution Submitted by Gautam    
Rating: 2.4000 (10 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution Indeed wrong: ice is faster, here is why | Comment 19 of 21 |
Interesting debate and question.  My skills are such I can play judge here.  To wit: the people who disagree with the solution are correct.  Here is why.  The cooling mostely occurs due to convection.  Without a strong gravitational field, little cooling occurs.  The flow rate is probably proportional to the differences in density between hot and cold regions.  The oil case, once below the oil's boiling point, results in delta-rho's of ~2.  The water case results in delta-rho's of ~100.  So you get faster convection with water.  In other words, the steam speed is much faster than the hot oil speed.  The situation reverses itself in strange cases, such as if you moved the steel very rapidly through the oil.
  Posted by Jason Taylor on 2005-08-03 05:56:57
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (9)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information