In collision that are categorized as elastic, the total kinetic energy of the system is preserved such that,
KE1 = KE2
The kinetic energy of the system before the collision is solved below.
KE1 = (0.5)(25)(20)² + (0.5)(10g)(15)²
KE1 = 6125 g cm²/s²
This value should also be equal to KE2, which can be calculated using the conditions after the collision.
KE2 = 6125 g cm²/s² = (0.5)(10)(22.1)² + (0.5)(25)(x²)
The value of x from the equation is 17.16 cm/s.
Hence, the answer is 17.16 cm/s.

When two bodies collide with each other in the absence of an external force, then the total final momentum of the bodies is equal to their total initial momentum.
The 'net' force acting on the box is (9 - 3) = 6 newtons
in the direction that Carlos is pushing.
Force = (mass) x (acceleration)
6 = (3) x (acceleration)
Divide each side by 3 :
<em>2 m/s² = acceleration</em>
Potential Energy= 24m * 14kg * 9.8N/kg = 3292.8J