In article ,
Percival P. Cassidy wrote:

Depending on your usage of the info it might be 0.75*(2pi) or

4.712388980385 radians per second.

Radians/sec. was the unit I assumed it would be, but I didn't bother
with the calculation

I prefer furlongs per fortnight (measured at the outer edge, of
course).

Since records can vary in diameter, this would require having at least
one reliable reference standard for the industry to work from. Like
the classic metric standards for length and weight, it should be of a
stable, noncorroding metal, kept in an inert atmosphere in either
Paris or Greenwich.

Gives new meaning to the term "platinum record", doesn't it?