What did they change in tennis balls?

Answer 1

They improved them a lot! If your question would be more specific, it would be easier to answer. The tennis balls used to be wads of hair or wool wrapped in stuff, but now they are more rubbery for bounce. I don't know exactly how.

Answer 2

The pressure in tennis balls has been reduced and the size of tennis balls has increased to take away some of the advantages derived from modern rackets, which enables players to generate tremendous power without extra physical effort.

Answer 3

Old tennis balls have been used before, causing them to be worn in. New tennis balls have never been used before and easier to play with. It takes experience playing tennis to be able to tell the differences in old and new balls while playing. Otherwise, you can just tell by sight. New tennis balls are a very bright neon color and very firm, where old ones are darker in color and usually have less fuzz on them. Older tennis balls may also be slightly deflated.

Answer 4

Tennis balls are hollow. The skin made out of two hemisphere bits of rubber and two dog boned shaped fur, which help make the ball more aerodynamic.