Recent content by paco1955

heat naturally flows from a greater to a lesser temperature gradient until there is no more difference in temperature. for example, if i drop an ice cube in a cup of hot water (in a closed system), heat naturally flows from the hotter body of water to the cooler ice cube until both bodies of...

it is the change in entropy that ultimately provides us with the answer to why systems will naturally evolve in one direction with time and not the other: systems always evolve in time in such a way that the total entropy of system + environment increases. If you observe a system in which the...

let there be given a stationary rigid rod; and let its length be l as measured by a measuring-rod which is also stationary. we now imagine the axis of the rod lying along the axis of x of a stationary system of co-ordinates, and that a uniform motion of parallel translation with velocity v along...