Answer
a. Yes, inelastic head-on collision of two objects with equal momenta.
b. No
Work Step by Step
a. Yes. An inelastic head-on collision of two objects with equal momenta
will result in both being at rest after the collision (all the initial kinetic energy of the system is lost). The kinetic energy is converted to other forms of energy.
b.
Since there is no friction, no external force is acting on the system, so no momentum will be passed to the surroundings (the initial momentum of the system is not lost).
