Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Pastimes : Neocon's Seminar Thread -- Ignore unavailable to you. Want to Upgrade?

To: one_less who wrote (763)	5/28/2003 6:35:44 PM
From: TimF	Read Replies (1) \| Respond to of 1112

You just said that you must generate energy to get light. So what was something else, becomes light. Once generated does the light shine eternal or is it converted to something else? Energy is generated by converting matter, or sometimes one form of energy is change to another and energy is said to have been generated when all that happened is that it changed (for example electric power "generated" from solar cells or from dams). In a light bulb electric energy is converted in to light and heat. Most of the light either gets absorbed by matter near it (converting the energy to heat), or gets scattered (broken down in to more smaller bits of energy, most of which eventually get absorbed. So the energy is changed from light to heat. The heat is relatively small and is harder for people to notice then the light. If the energy of the light shining for a time was enough to raise the temperature of the room 1/10th of one degree most people would not be able to notice it. Of course it could be measured through instruments. And assuming no other source of warming they would see the room cool down again, but that wouldn't be the energy disappearing it would rather be the energy (specifically heat) spreading from the room to places outside the room. You haven't defined energy. You didn't ask for a definition. I'm sure any dictionary or physics text book would have one. ...so the default argument for science is that there is no separate entity called energy. If by "there is no separate entity called energy", you mean there is nothing called energy that is separate from the different forms of energy (heat, light, ect.) that energy can take then I agree. If you mean there is nothing that you can call energy then I disagree. The heat and the light and the other forms are energy. Its not that you have light and have something associating with the light which we call energy, no the light itself is energy. But then energy is also defined as the capacity to do useful work. If you look at it that way then the "heat energy" is different from heat. In a closed system with a uniform steady temperature of 100 degrees Kelvin you have heat but no potential to do useful work, or at least no potential just from the heat of the system. Differences in temperature would give you energy if you use that definition not just heat. Also by that definition energy can be destroyed. That same closed system could have had great differences in temperature before, over time the temperature equalized. Those great differences could have been tapped to do useful work but once they are gone the "capacity to do useful work" is also gone. Tim