BASEBALL & SOFTBALL MOVIES

 Can the spin of a baseball reverse direction when the ball bounces?     Bounce 1      Bounce 2

 PITCHING

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 Closeup of the finger action, in slow motion, when pitching a fastball and a slider.   The ball spins in the direction that the fingers pull on the ball (as expected).

 How to pitch a ball with a sideways break of six feet or more. Step 1: Polish one side of ball Step 2. Roughen other side or glue a loop of string around that side Step 3: Reduce ball mass to about 15 or 20 gram. Step 4: Hold ball with smooth side on your right. Step 5: Throw a fastball straight at camera (with backspin).

 My pitching effort is of no practical value (like a lot of physics) but at least it demonstrates  the physics behind the swing of a cricket ball with its rough and smooth sides and seam. How about a baseball?  Does it have a rough and a smooth side or doesn't it? What if it is spinning? That might be of practical interest, at least for knuckleballs.

 Here is a 100 mm diameter polystyrene ball with a baseball seam glued to the ball. It breaks 90 cm over a distance of 5 m if the seam is aligned properly, otherwise there is no break or a smaller break.   90 cm break            70 cm break         no break      (all 300 fps)

 BATTING

 The center of percussion (COP) of a hand held bat is not the same as the COP of a freely suspended bat. This movie shows that the axis of rotation of a hand held bat is near the wrists (regardless of the impact point on the bat). The COP is NOT the sweet spot of a bat.

 Low speed baseball bounce, filmed at 1000 frames/s

 Why are baseballs and softballs so hard? Softer balls would reduce injuries, help prevent bats breaking and reduce the trampoline effect. The Kenko ball here (a hollow, rubber ball) is 10 times softer than an adult baseball and 3 times stiffer than a tennis ball. It is used in youth leagues in Japan, Australia etc.

 How fast can you spin a 12 inch softball?     1000 rpm?  (12 in is the circumference!)

 Cricket ball colliding with a baseball to see which is heavier.

 Swing speed vs bat weight. Light bats can be swung faster. By how much?

 Hoop modes of a hollow bat (the ping sound).

 Measuring outgoing ball speed at different  impact points on a bat