a. The collision is not an elastic collision
b. The muzzle velocity is 2.1m/s
An elastic collision is a type of collision where both kinetic energy and momentum are conserved. The objects rebound off each other without any loss of total kinetic energy.
Since in this case , the two colliding object stock together and moves together with a common velocity.
The collision in this case is called inelastic collision.
The muzzle velocity is calculated form the equation of motion
v² = u² - 2gh
v = 0
0² = u² - 2 × 9.8 × 0.219
u² = 4.29
u = √4.29
u = 2.1 m/s
