Tennis is comprised of many specific, yet integrated components, all of which are easily broken down into the basic laws of physics. One such component is the serve. The ball, ideally, is thrown directly upward for so that it reaches its velocity reaches zero, one second after it is released and the ball reaches height approximately one foot higher than arm's length. This would mean that a correct toss would be thrown at an initial velocity of approximately 10 meters per second. Higher tosses create a more favorable angle to send the ball over the net, especially when coupled with persons of height.
The service swing must be exactly as precise in order to have an effective service. The racket provides both a forward and downward force on a powerful serve. The racket must accelerate the ball to a minimum forward velocity of 40 m/s, if and only if no downward force is applied except gravity. Shots must travel a minimum of 39 ft to reach the net, which is approximately two ft. off the ground. Serves with no downward force are usually undesired during competitive play, as they are not travelling with a high enough velocity to challenge the opponent. The fastest serve ever recording was by Andy Roddick at 249.5 km/hr (155 mph). This ball travelled the entire length of the court in 1.12 seconds as a legal serve.
After service, the ball is returned to the server by stroking through the ball with the racket. Strokes are either forehand or backhand in nature and use the lever created in both the arm and the shoulder to create the momentum needed to counteract the motion of the served ball. Backhand strokes are weaker than forehand strokes, due to the strength of the muscles used during the stroke and the rotational ability of the levers in the opposite direction. The other main shot in tennis is the volley. Volleys are not a stroke of the racket, but only the use of the racket to block the ball, in a partially elastic collision. The lightweight racket strings absorb little momentum from the ball, creating the scenario for a semi-elastic collision
Serves and strokes also can travel with a considerable amount of spin. The ball, when given this added torque, creates a low air pressure and high air pressure zone around it, which gives the ball a curved path instead of instead of a predictable straight line. The curved path is less noticeable in tennis than in other ball sports, such as baseball and softball, as the ball travels shorter distances and goes at higher velocities. The spin of the ball is noticeable when in tennis when the ball hits the courts and the spin gives the ball a newer pointed trajectory.
Three types of spins cause these varying bounces: topspin, backspin, and sidespin. Sidespin is mostly noticeable while serving, when the spin can be controlled the most, and causes correlating left and right bounces. Topspin is created when the racket is carried over the ball, which gives the ball a forward rotation. Topspin shots cause low, fast bounces, which are the most difficult to catch up to. Backspin shots are hit when the racket is slide under the ball, creating a slower shot. This shot bounces back towards the athlete that hit the ball, and may result in his opponent not being able to reach it in time.
These three shots need are hit with the racket in an angular position. Backspin shots tend to be more accurate when in the middle of the court, and require a less steep angle for execution. Topspin shots are better hit from the baseline, and require rotation to the angle while mid-shot. Sidespin shots are hit like upright backspin shots, but work only when the ball is high and overhead.
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ReplyDeleteMight try spacing out the paragraphs. Tab doesn't really work, but you can just hit return and start a new line after each paragraph. Otherwise, it's a little jumbled and hard to read.
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