ISEN-ASTC-L is a service of the Association of Science-Technology Centers
Incorporated, a worldwide network of science museums and related institutions.
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Well... a simplified description:
The energy under discussion begins as chemical potential energy
(hydrogen). The hydrogen fuses, releasing nuclear energy. This emitted
energy is radiated in a broad spectrum, to be intercepted by among other
objects, your car. The material of your upholstery and the gas molecules
in the car absorb some frequencies of this energy, particularly in the
visible and infrared frequencies. (uv and most energy more energetic
than that is blocked by the glass. Below the infrared, the light will
not significantly interact with the molecules in the car.) The energy
absorbed by the molecules can be re-emitted as radiant energy
(relatively uncommon) or dissipated between molecules as heat (also
known as rotation and translational energy). As the heat increases, the
surrounding gas is heated, primarily by convection, but also by
radiation if the upholstery gets hot enough for that to be a significant
contributor.
Sense one, it is not new heat, the sun was the original object that
released the heat.
Sense two, it is new heat, the energy was useful light before the car
transformed it into heat.
Sense three, the heat energy from the car is waste heat, good for
nothing unless it is cold outside the car or you are into hobo cooking.
Isn't thermodynamics fun.
Tom Twardowski.
-----Original Message-----
From: Informal Science Education Network
[mailto:[log in to unmask]] On Behalf Of martin weiss
Sent: Wednesday, September 06, 2006 2:15 PM
To: [log in to unmask]
Subject: Re: heat: a thought exercise
ISEN-ASTC-L is a service of the Association of Science-Technology
Centers Incorporated, a worldwide network of science museums and related
institutions.
************************************************************************
*****
>ISEN-ASTC-L is a service of the Association of Science-Technology
>Centers Incorporated, a worldwide network of science museums and
>related institutions.
>***********************************************************************
******
>
>I was chatting with a host at a wine-tasting event this past weekend in
>Sonoma, and as soon as he found out I was involved in the science
>museum field, he posed a challenge, and it threw me to the extent that
>I said I'd post it to the ASTC list and see where the chips fell.
>
>*****
>Here's the exercise:
>
>Imagine that you've parked your car outside on a hot summer day. When
>you open the doors after a couple of hours, you're blasted with the
>heat that has built up inside. Is this "new heat"?
No, it is not "new heat". Energy, and heat is a form of energy, can
be converted to different forms but not created or destroyed, I
think. But then I am a biologist.
Martin
> If so, could this (gazillions
>of cars sitting around) theoretically contribute to an excess of global
>heat (global warming)? To add to the exercise, imagine that this is
>taking place 10 million years ago, without the variables brought on by
>chemicals in the atmosphere.
>*****
>
>If you're like me, you'll have a knee-jerk reaction to this exercise,
>but then you may step back a mental notch and find yourself asking more
>questions than you thought you started out with, so I will stop here
>and not pollute the discussion with any of my own initial thoughts.
>
>My new friend is looking for equations and the like to prove the point
>- one way or the other - game on!!!
>
>***********************************************************************
>More information about the Informal Science Education Network and the
>Association of Science-Technology Centers may be found at
>http://www.astc.org. To remove your e-mail address from the ISEN-ASTC-L
>list, send the message SIGNOFF ISEN-ASTC-L in the BODY of a message to
>[log in to unmask]
--
Martin Weiss, Ph.D
Vice President, Science
New York Hall of Science
47-01 111 th Street
Corona, New York 11368
718 699 0005 x 356
***********************************************************************
More information about the Informal Science Education Network and the
Association of Science-Technology Centers may be found at
http://www.astc.org. To remove your e-mail address from the ISEN-ASTC-L
list, send the message SIGNOFF ISEN-ASTC-L in the BODY of a message to
[log in to unmask]
***********************************************************************
More information about the Informal Science Education Network and the
Association of Science-Technology Centers may be found at http://www.astc.org.
To remove your e-mail address from the ISEN-ASTC-L list, send the
message SIGNOFF ISEN-ASTC-L in the BODY of a message to
[log in to unmask]
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