Speaker 1: Welcome to brain Stuff from how stuff marks dot com
Speaker 1: where smart Happens. Hi, I'm Marshall Brain with today's question
Speaker 1: in baseball, how does a picture throw a curve ball?
Speaker 1: A successful major league batter it gets a hit only
Speaker 1: about thirty percent of the time he comes to bat.
Speaker 1: But one of the ways pitchers lowered these chances even
Speaker 1: further is by throwing a curveball. A curveball is a
Speaker 1: pitch that appears to be moving straight toward the plate,
Speaker 1: but that is actually moving down and to the right
Speaker 1: or left by several inches. Obviously, a pitch that curves
Speaker 1: is going to be harder to hit than a fastball
Speaker 1: that's moving straight. There are two basic factors involved in
Speaker 1: creating a curveball. First is proper grip, and second is
Speaker 1: air resistance. Any baseball pitch begins with how the picture
Speaker 1: grips the ball. To throw a curveball, a picture hold
Speaker 1: the baseball between his thumb and his index and middle fingers,
Speaker 1: with the middle finger resting on the baseball seam. When
Speaker 1: the picture comes through his motion to throw the ball,
Speaker 1: he snaps his wrists downward as he releases the ball,
Speaker 1: which gives the ball top spin. If the picture throws properly,
Speaker 1: the back of his hand will be facing the batter.
Speaker 1: At the end of the motion, the ball will break
Speaker 1: down and away from a right handed batter. If thrown
Speaker 1: by a right handed pitcher, The spinning action created when
Speaker 1: the pitcher releases the ball is the secret behind the
Speaker 1: curve ball. This spinning causes air to flow differently over
Speaker 1: the top of the ball than it does under the ball.
Speaker 1: The top of the ball is spinning directly into the
Speaker 1: air and the bottom of the ball is spinning with
Speaker 1: the air flow. The air under the ball is flowing
Speaker 1: faster than the air on top of the ball, creating
Speaker 1: less pressure, which forces the ball to move down or curve.
Speaker 1: This imbalance of forces called the Agnus effect, named after
Speaker 1: physicist Gustav Magnus, who discovered in eighteen fifty two that
Speaker 1: is spinning object traveling through liquid is forced to move sideways.
Speaker 1: Adding to the air pressure exerted on the ball. Are
Speaker 1: the hundred and eight red stitches that hold the cover
Speaker 1: on the ball. Because they're raised, the stitches increase the
Speaker 1: amount of friction created as the air passes around the
Speaker 1: ball and places more air pressure on top of the ball.
Speaker 1: A well thrown curveball can move as much as seventeen
Speaker 1: inches either way. If you've ever seen a batter jump
Speaker 1: out of the way of a baseball that ends up
Speaker 1: crossing over the plate, you've seen a great curveball. Be
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