
The Physics of a Tennis Ball’s Spin - Rifu
http://www.wired.com/2015/09/mind-bending-physics-tennis-balls-spin/
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jimworm
Misleading title - the article asserts that spin wins matches without
describing the physics at all. It's a barely-veiled advertisement for Wilson's
rackets.

In tennis, the spin that "wins matches" is the topspin. In a topspin, the
Magnus effect generates downwards lift, allowing the ball to be hit forwards
faster and still land in the court than if downwards acceleration was provided
by gravity alone. Without spin, unlimited-speed shots can only be hit at
heights where the ball has near line-of-sight with the opposite court. Since
hitting the ball faster than your opponent can get to it is what wins points,
that's why spin wins matches.

But tennis is hardly the poster-boy for the Magnus effect. Table tennis has a
small and raised court, and a high speed/mass ratio, which makes it apply the
Magnus effect more completely than any other sport. Spin is used to to
generate lift for long slow defensive shots, to attack from far below table
level, and to alter ball direction in flight. Table tennis players require a
good "feel" for all aspects of the Magnus effect in order to improve much more
beyond beginner level, and no mid-level amateur player can ever get away with
not thinking about it.

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Nicholas_C
The Magnus effect is extremely important (and fun) in golf as well.

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cromulent
There's an excellent video submitted here:

[https://news.ycombinator.com/item?id=9915197](https://news.ycombinator.com/item?id=9915197)

about the Magnus effect. Quite simple and amazing.

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andy318
The author says that Wilson's new racquet with Spin Effect technology
_doubled_ the spin on his shots compared to his normal racquet. Now that
sounds mind-bending!

Especially when Wilson's site claims that technology provides the benefit of
10% more spin - [http://www.wilson.com/en-us/tennis/spin-
effect/innovation/](http://www.wilson.com/en-us/tennis/spin-
effect/innovation/)

