physics in tennis!

While playing tennis last weekend, I noticed that a great deal of physics is involved in the sport. It was quite windy on that particular day, so the motion of the tennis ball was constantly affected by air resistance, which we learned how to calculate in class. Personally, I don't like playing in the wind because it is a lot harder to control the ball and to hit the ball cleanly. Anyway, I also found that friction acts on the ball when it hits the ground, especially when there is a lot of backspin on the ball, causing it to stay lower on the ground. This leaves the ball on the ground for a longer amount of time as opposed to topspin, so there is more friction occurring when the ball has backspin. Also, constant forces are being applied when the racket hits the ball, and then the ball is at all times influenced by the force of gravity. Forces are not only acting on the tennis ball as the players are also influenced by outside forces. This would include weight, a force directing straight downwards, as well as a normal force, perpendicular to the ground directed upwards. Even friction is present when the players run as their shoes come in contact with the ground. Physics is everywhere!