Explanation:
Given that,
Initial speed of the billiard ball 1, u = 30i cm/s
Initial speed of another billiard ball 2, u' = 40j cm/s
After the collision,
Final speed of first ball, v = 50 cm/s
Final speed of second ball, v' = 0 (as it stops)
Let us consider that both balls have same mass i.e. m
Initial kinetic energy of the system is :

Final kinetic energy of the system is :

The change in kinetic energy of the system is equal to the difference of final and initial kinetic energy as :
So, the change in kinetic energy of the system as a result of the collision is equal to 0.
Answer:
0.631 m
6.53315 J
Explanation:
m = Mass = 2.47 kg
v = Velocity = 2.30 m/s
k = Spring constant = 32.8 N/m
A = Amplitude
In this system the energy is conserved

The amplitude is 0.631 m
Mechanical energy is given by

The mechanical energy is 6.53315 J
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