electro-Physics: 17.3409 volts

[gordonjcp at gjcp.net]

> I don't actually know where 50 and 60 Hz came from, nor 100 and 115
> and 220 and 240 volts.  There may be some ancient justification in the
> tinkerings of various 19th century engineers, but it seems to me it
> makes most sense simply to view them as random numbers.
>
>       paul

With a simple two-pole machine, 50Hz is acheived at 1,500rpm which is a
nice round(-ish) number.  Obviously a six-pole machine will produce a 50Hz
three-phase supply at the same speed, and 60Hz at 1,800rpm.

Now, 1,500rpm is quite a good speed for steam engines and the like, and
it's possible to make direct-drive hydroelectric turbines that run at that
speed, very efficiently.

Gordon.