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BAsM
Nov29-09, 04:42 PM
When you throw a ball in the ground you give it kinetic energy but because of the friction with the ground the ball come to rest.
Where is the kinetic energy goes?!
i know that the law of conservation of energy states that this conservation happened in closed-systems.
but anyone has ideas about where this waste energy goes if we considered the whole universe as a closed-system?

mathman
Nov29-09, 05:38 PM
The friction energy goes into heat.

BAsM
Nov29-09, 05:42 PM
and where is the heat go

SystemTheory
Nov29-09, 05:52 PM
The kinetic theory of heat assumes temperature is caused by microscopic vibrations and motions. The energy dissipates into random motion on a microscopic level, which we measure as an increase in temperature.

http://www.phy.cuhk.edu.hk/contextual/heat/tep/trans01_e.html

russ_watters
Nov29-09, 06:42 PM
and where is the heat go Everywhere. It dissipates.

jsea-7
Dec1-09, 07:23 AM
The friction energy goes into heat.

The kinetic energy that you give the ball (through throwing it) would disperse through many forms of energy; also suggested by russ_waters in the previous message. But I would not speculate that the main form of energy that the kinetic energy of the ball is dispersed to, is mainly through heat energy; due to the fact that it is not the main energy. I would like to outline that most of the kinetic energy of the ball as it hits the ground of the Earth, will in fact simply be transfered as kinetic energy acting upon the Earth in which ever direction the ball hits. Now why don't we notice this transfer of energy, or in other words why will we never notice a transfer of energy from the ball to the Earth? Well it is simply due to the size and mass of the ball compared to the Earth; the ball is just to small to create a large enough effect that is noticeble.:smile:

dE_logics
Dec1-09, 08:03 AM
Check out "Conservation Laws" by Benjamin Crowell available under creative common license.