The two inches of ice on the Apollo Ohno ad where he is skating in one direction and the ice is a disc turning in the other is mostly misleading because the ice is formed on a solid bed of concrete. Some older rinks support the ice on a bed of sand with the cooling pipes running through the sand. The ice is definitely not floating on water. You are correct that it is 1-2 inches thick.
Bob at PC
Figure Skating Judge
________________________________________
From: phys-l-bounces@carnot.physics.buffalo.edu [phys-l-bounces@carnot.physics.buffalo.edu] On Behalf Of Bernard Cleyet [bernardcleyet@redshift.com]
Sent: Sunday, February 21, 2010 3:25 PM
To: Forum for Physics Educators
Subject: [Phys-l] Torque, angular momentum, dissipation, etc. in an advert.
The following advert, tho well done and exhibits physical principles, is also very misleading, and, therefore, perhaps harmful if not accompanied by a discussion. It's currently being praised by members of a HS physics list, who will class room use it.
Here's the link:
YouTube - Record
Also posted here:
The Blog of Phyz
Am I wrong? I calc. the I (orJ) to be about five million kg m^2 [assuming the skater is two meter tall the ice disk has a radius of fifteen m and is > 0.05 m thick. Two inch ice will not support a walking person -- the skater is more than walking!] Also the dissipation must be enormous!
Near the end the disclaimer: "Screen images simulated"** is in very small type -- I didn't see it until the fourth viewing and no poster has mentioned it -- one suggest it might be "real"; the others haven't commented.