Step-by-step explanation:
When the student pushed the puck toward the opposite side of the game board expecting it to continue all the way to the other side but the puck failed to slide all the way to the opposite side of the board. This is because the collision was an inelastic collision in which the kinetic energy of the motion is not conserved and it gets lost in the form of heat and molecular vibrations.
Only in case of perfectly elastic collision both the linear momentum and the kinetic energy are conserved.