animation explaining Joule's apparatus and his calculations. https://www.youtube.com/watch?v=5yOhSIAIPRE
Harry On Tue, Jun 6, 2017 at 11:43 PM, H LV <hveeder...@gmail.com> wrote: > > > Joule's apparatus used a spindle with paddles which was turned by a > falling weight outside the calorimeter. The motion of the falling weight > did not result in the generation of potential energy. It only resulted in > the warming of the water inside calorimeter. However, if the falling of the > weight were to wind up a spring in addition to turning of the paddle then > the same energy input - in the form gravitational potential energy (i.e. > the weight time the height through which the weight falls) would warm the > water AND store energy in the spring. According to Joule the amount of heat > generated is only a function of how far the weight falls. It is not a > function of how quickly it falls, so even if the spring slows the descent > of the weight the calorimeter will read the same rise in temperature with > or without the spring attached. > > This thought experiment demonstrates how two systems can have the same > energy input and generate the same temperatures but one can store energy > and the other can't. > >
