Final answer:
The momentum of a baseball changes when struck by a bat due to the impulse applied by the bat, which changes the ball's momentum while conserving the total momentum of the system. The change is a result of the force exerted over the time of contact. Total kinetic energy may not be conserved as it can be transformed into other forms of energy during the collision.
Step-by-step explanation:
The momentum of a baseball changes dramatically when struck by a bat because of the concepts of impulse and conservation of momentum. In physics, when a force is exerted on an object over a period of time, it causes an impulse, which changes the momentum of the object. If we consider the baseball and the bat as a system, the total momentum of the system is conserved during the collision, even though the momentum of the ball alone is not. The bat applies a force to the ball, imparting a change in momentum, which is also known as an impulse. This impulse is the product of the average force applied by the bat and the time duration over which this force acts, as shown by the equation FΔt = mΔv, where F is the average force, Δt is the time interval, m is mass, and Δv is the change in velocity.
While the baseball's velocity and direction change, the bat and player feel a corresponding change in momentum to conserve the overall momentum of the system. The kinetic energy, however, may not be conserved during such inelastic collisions. Some of the kinetic energy can be transformed into other forms of energy, such as heat and sound, or used to deform the ball and bat.