Dr. Rod Cross, an avid tennis fan who earned his PhD in plasma physics from Sydney University, co-authored the book Technical Tennis: Racquets, Strings, Balls, Courts, Spin and Bounce with ...

Equipment: A tennis ball on a string. What it does: Swing the ball on the string to show circular motion. Release the ball to show the instantaneous velocity of the ball. Concepts Demonstrated: ...

A batsman sees a spinning ball midway through its flight ... which causes the ball to dip in its flight. Having the ball on a string is a phrase used quite often for it. Batsman comes down the ...