Is 52 kilometers per hour as fast as a Fastball (baseball)?
It's about one-third as fast as a Fastball (baseball)
The speed of a Fastball (baseball) is about 150 kilometers per hour.
(a.k.a. rising fastball, a.k.a. cross-seam fastball, a.k.a. heater, a.k.a. hummer, a.k.a. smoker; for four-seam grip) (major league average)
The average speed of major league fastball pitch is 150 kph. When up against the quickest professional fastball pitchers, a batter may have less than 0.4 seconds to react to a pitched ball.
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