Date: Tue, 6 Jan 1998 17:48:31 -0800 (PST)
From: Gene Thompson <gthompso@ccsf.cc.ca.us>
To: Pinhole Listserv <pinhole@exploratorium.edu>
Subject: Re: wave reflection
In-Reply-To: <58316b7.34b1bb4e@aol.com>
I've always gotten sunburned through window glass -- both house and car.
So, whether or not the theory states that glass is supposed to block UV,
in practice I know it doesn't.
Ellen Koivisto
On Tue, 6 Jan 1998, Pinhole Listserv wrote:
> There are two things about waves that have been driving me crazy. First, how
> can I explain to my students that a wave travelling along a medium like a
> spring that is loose on one end (or fixed to a "loose" medium) will reflect
> with no inversion. They'll accept wave reflection so as to conserve energy,
> but no inversion after they can visualize a Newton's third law description of
> a reflected wave being inverted at a rigid barrier makes them very unhappy.
> Got a good explanation?
> Second, so (window) glass is opaque to UV, at least that's what I've thought.
> My students insist they get sunburns through car windows and I tell them
> they've got poison ivy. Is glass opaque to all UV frequencies? How thick
> does it have to be?
>
>