Just finished watching the great Wimbledon Men’s Singles final, where Goran Ivanisovic won with 20+ aces. The commentator mentions that “grass courts favor hard servers like Ivanisovic, because they’re so fast.”
I’ve heard this before, but it still puzzles me. By “fast” I presume they mean the ball bounces off the court with the least depreciation in velocity, which I figure would come from bouncing off a harder surface than a “slow” court. Same as how a superball bounces harder off concrete than a wood floor.
So why would grass, which is packed dirt with a cushion of tiny leafy blades, be “harder” and “faster” than clay or asphalt? Am I looking at the physics all wrong? Does grass have some sort of “bounce” effect from its softness? Does the precise squishiness or texture of the ball have something to do with it?
Any insight or good guesses apprciated.
My profoundest apologies for triple-posting. It was my computer, I swear. If a moderator could please delete the duplicate threads, I would appreciate it. Thanks.
(slinks away)
I think where you are going wrong is in failing to distinguish between horizontal and vertical effects. When people talk of a tennis surface being “faster” they are talking about horizontally, not vertically. Consequently, it’s not how hard the surface is, (which is what affects how well a superball bounces) it’s how slippery it is.
Grass gives less bounce in the vertical, and less grip to the ball in the horizontal than a slow surface like clay. Clay grips the ball such that horizontal speed tends to get converted into height of bounce. A hard flat shot that bounces on clay tends to come off a little slower (horizontally) and higher, but the same shot on grass comes off comparatively lower, but with little loss of horizontal speed.