Is rate of collision and frequency of collision the same ? In what ways are they different ?
Collisions of WHAT? And in what context? I would say that yes, they are likely to be the same but "rate" is a bit vague whereas "frequency" is a more solid technical term relating to how often something occurs over and over again. That is "rate" could be used to mean speed and other things (as in rate of decay, rate of travel, etc.) in addition to a "rate of collision" (which in any case sounds very awkward)
Collisions of molecules. Can the terms be used interchangeably? Thanks.
Ah ... well that's a bit of a different story. Collisions of molecules are not periodic motion so I think "rate of collisions" is better than "frequency of collisions" since frequency connotes periodic.
On the other hand "frequency" connotes a time reference where "rate" (from the root word "ratio") connotes something that can be more generic (e.g "a defect rate of 10 problems per car coming off the assembly line"). One might want to use the more specific term rather the more generic when describing a time-based rate.
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