First Law - The external forces of gravity and drag act on the ball and bring it to an eventual stop.
Second Law - We know the resulting acceleration of the tennis ball based on the force exerted on it by the racquet, and it weight.
Third Law - The force exerted on the ball by the racquet is equal to the force exerted on the racquet by the ball.
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Gravity
Gravity is one of the major forces that acts to reduce the ball’s vertical component.
The typical magnitude of the force of gravity on a tennis ball can be calculated by using the formula F = mg, which, when using a standard ball, gives you 0.56 N.
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Drag
Drag is one of the major forces that act on the ball that limit its horizontal component.
To calculate the drag you can use the equation:
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Impulse
Impulse starts when the ball first comes into contact with the strings. The impulse is very low at this point.
The point of maximum impulse is when the strings are the furthest from their initial position.
As the ball leaves the strings, and doesn’t touch them, the impulse reverts to 0.
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Magnus Effect
The Magnus Effect is an instrumental part of all sports with a ball and a bit of spin.
Magnus Effect: “As a spinning ball moves through the air, it spins a boundary layer of air that clings to its surface as it travels along. On one side of the ball the boundary layer of air collides with air passing by. The collision causes the air to decelerate, creating a high-pressure area. On the opposing side, the boundary layer is moving in the same direction as the air passing by, so there is no collision and the air collectively moves faster. This sets up a low-pressure area. The pressure differential, high on one side and low on the other, creates a lift force (the Magnus force) that causes the ball to move in the direction of the pressure differential.”
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Topspin
Topspin occurs when the racquet slides over the ball.
During this shot, the Magnus Force is downwards.
The Magnus Force makes the ball dive into the court, allowing for players to increase the speed of their shot without having to worry.
The downward Magnus Force also makes the ball bounce higher.
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Backspin
Backspin occurs when the ball slides under the ball.
Since the Magnus Force is directed upward during this shot, the ball gets a “floaty” effect.
The upward Magnus Force also reduces the height the ball bounces.
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Flat
A Flat Shot occurs when the racquet strikes the ball at its midpoint.
During this shot, negligible Magnus Force exists.
The only thing restricting the ball’s horizontal component during this shot is drag, which shows the high variability of the shot.