What is the final speed and angle of a ball hit by a baseball bat at 45 degrees?

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The discussion centers on calculating the final speed and angle of a baseball after being hit by a bat at a 45-degree angle. The initial conditions include a ball approaching at -30 m/s and a mass of 0.150 kg. The user attempts to apply momentum conservation principles but struggles with the bat's influence, noting that it is not a free body due to its connection to the batter. There is confusion regarding the application of momentum conservation in this scenario, as examples in the user's textbook provide different parameters. The conversation highlights the complexities of momentum calculations in real-world scenarios involving external forces.
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Hi,
Sorry for another momentum question I want to be sure.

Homework Statement


A ball who is coming at 180 degree is hit by a baseball bat at 45 degree in the opposite direction. The final speed of the ball and the angle is unknown and this is want we search.

N*S=kg *m/s
I=5 N*S= 5 kg*m/s
Initial ball speed Vo=-30m\s
Bat speed =Vb
Masse M=0.150 Kg


Homework Equations


So I suppose that since the ball is hit at 45 degree
the impulsion will be
5 kg*m/s*cos(45)=the horizontal vector and 5 kg*m/s *cos(45)=the vertical vector


The Attempt at a Solution


5 kg*m/s*cos(45)= 3.5 I
5 kg*m/*sin(45)= 3.5 J
(3.5 I + 3.5J) kg*m/s= 0.150kg(Vb- ( - 30I) )m\s
(23.3 I + 23.3 J )m/s= (Vb+30I) m\s
(-6.7 I + 23.3 J ) m/s = Vb Not in the opposite direction ?
For the final speed = -6.7 I+28J -30I= -36.7I +28J
hmm the baseball bat have hit the ball but not and the right direction, something most be wrong
thank you
 

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Conservation of momentum of the bat and ball does not apply here. The reason is that the bat is not a free body. It is connected to the batter who is, in turn, connected to the earth.

AM
 
Hmm any ideas how to solve ?
I don't understand Andrew, there are some exemples like this one in my book, but they give the final speed and the initial speed ( the momentum is to find). What is the difference ?
 
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