To solve this problem we will apply the principle of conservation of energy and the definition of kinematic energy as half the product between mass and squared velocity. So,
Here,
m = Mass
V = Velocity
Replacing,
Therefore the final kinetic energy of the two car system is 72.6kJ
The concept of momentum tells us that it is equivalent to the product between the mass and the velocity of the object, that is to say that in general it can be written as
Where,
m = mass
v = Velocity
Our values are given as,
Replacing we have that,
Therefore the magniude of the momentum of the pitched baseball is