Movie speed & TV

IIRC cinematic film is shot at 24 fps
US TV runs at 30 fps
European TV runs at 25 fps

So how do they show movies on TV?
Supplementary question:
Is it more than coincidence that the TV rate is half the AC supply frequency in a given country?

I guess, they repeat some frames.

Yes.

It’s called 3/2 Pulldown:

A device called a telecine takes the film and extrapolates the extra frames needed. It takes part of the frames and makes new ones. This site explains the process pretty well.

As for your supplementary question, you’re right, it’s no coincidence. The AC frequency in fact controls the field rate of the TVs. IIRC, it was a political decision in Europe to prop up the copper mining industry by building a 50 Hz electricity system. We didn’t do that in America, so we used 60 Hz, which is why we have different frame rates on TV.

Interesting link Fear Itself, thanks.