Setting aside the physiological issues, force is applied to a Baseball to accelerate it. The ball rotates in flight according to any "spin" (which is torque) applied to it as it is released. It's shape (particularly the seams) and the spin combine in its flight to apply forces that deflect it from a straight line path. Certainly gravity is pulling the ball down from the moment it is released. The analysis of fluid mechanics as it applies to the ball can become complex. Any breeze will also play a part. The batter applies a moving mass (the bat) to the ball to strike it (if he can), and accelerate it from the point of impact. We'll again see gravity clinging onto the ball as it leaves the bat, and we'll see more complex motion of the ball due to the way it moves through the air. Some spin may still be present on it after it leaves the bat, either because of the original forces that set in motion, or some spin applied by virtue of the ball impacting the bat off center, or a combination of the two.
The forces on the baseball are balanced when it's on the ground or on the shelf in the clubhouse, and unbalanced at all other times.
The forces cancel each other, at least externally.
gravity
Some are, some are not.
Some forces are: Sociocultural, economic, technological, legal and regulatory
gravatational forces' friction forces, .
gravatational forces' friction forces, .
internal and external forces.
There are some forces in nature whose ranges are very small. So small that they can only be felt at the microscopic level. One such forces is the nuclear forces. these forces are called nuclear forces because they are only dominant at the nuclear level.
Gravity and wind resistance.
Magnetism, friction, and reaction forces in general.
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