Originally Posted by julian
So why the "absolute symmetry of the ball" was brought into the discussion?
I do NOT understand the phrase "solid contact" either
Does "solid contact" mean collision of a rigid body with a rigid body?
We were talking about solid contact of the racquet with ball.
In post 519 I said, “If racquet velocity has normal component only (normal to string bed) and point of contact is sweet spot, you hit pure flat FH (forget about strings actions). Because of the absolute symmetry of the ball there always should be solid contact.
If racquet speed has tangential component only, there never will be solid contact.”
What is wrong with that?
If carpenter wants to hammer a nail, he also should create only normal component of the hammer velocity to get solid contact, but is not enough, because the nail doesn’t have absolute symmetry. The normal component of velocity must coincide with longitude axis of the nail to provide solid contact.