Re: Fwd: The Concrete Wheel
Duncan Chiu (dchiu@idt.net)
Fri, 02 May 1997 17:44:49 -0400
IraFrdmn@aol.com wrote:
>
> I think that I know the answer but I will check and wait until others have
> time to think about it.
> ---------------------
> Forwarded message:
> From: DADKB@CUNYVM.CUNY.EDU (Dan Davis)
> To: RFORMAN639@AOL.COM (Ron Forman)
> CC: irafrdmn@AOL.COM (Ira Friedman), ejf2@acpub.duke.edu (Eric Forman),
> fsawin@hypercon.com (Fred Sawin), thompson@utaphy.ph.utexas.edu (J.C.
> Thompson), btimmer@isi.edu (Brenda Timmerman), jan@extant.com (Jan Smith),
> jackarn@juno.com (Jack Arnow), F.Pleiter@phys.rug.nl (Frits Pleiter)
> Date: 97-04-30 05:10:33 EDT
>
> THE CONCRETE WHEEL
> [This problem is proposed by Victor J. Katz in a book review in
> the College Mathematics Journal, May 1997.]
>
> Suppose you are sitting in a ground level room, facing a square
> floor-to-ceiling window that is 20 feet on a side. A huge solid con-
> crete wheel, 100 miles in diameter, is rolling down the steet and is
> about to pass right in front of the window, from left to right. The
> center of the wheel is moving to the right at 100 miles per hour. What
> is the view, from inside the room, as the wheel passes by?
Ira,
How about a fleeting salesman's car? A portion of the sine curve? Or,
maybe a slow-moving parabola? (It took one hour to clear the object,
didn't it?)
For those of us who could not visualize a ratio of 52,800 to 1 (wheel to
window,) try this:
Move the window from right to left along a yardstick taped to the edge
of a big round table, making sure the stick is slightly higher than the
table. you can cut a small square off the edge of a piece of paper (that
is your wall and the window) and slid it along the stick.
What do you say?
duncan