Two pieces of clay collide and stick together. During the collision, which of these statements are true? (a) Only the momentum of the clay is conserved; (b) only the mechanical energy of the clay is conserved; (c) both the momentum and the mechanical energy of the clay are conserved; (d) the kinetic energy of the clay is conserved.
Solution 24DQ Step 1: When two pieces of clay are hit and stick together, the momentum of the system is conserved. That is, Pinitialfinal But, the energy is not conserved here because, the initial kinetic energy of both pieces will be used to heat up the system during collision. And some part will be lost as sound energy. So, initial energy final energy Conclusion The energy is not conserved during the collision but, the momentum is conserved. So, option (a) is correct.