How do they measure the speed of bowling (in Cricket), and speed of serving (in tennis) electronically?

I know they use sensors, but how? I need detais, if you can supply. Thank you.

Simple physics – distance over time (distance divided by time) multiplied by 100 equals speed.

The laser sensors can predict both measurements to extreme accuracy.

Quantum Physics may have other things to say on this matter but “Spacetime” is more for sub-atomic particles.
As Brenton (above) mentioned, the “Doppler Shift” can be used but there is no accurate way to measure momentum and position AT THE SAME TIME.
That is one of the greatest challenges of Physicists to this day.

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