Q.In the following table, every item on the left side can match with any number of items on the right hand side. Select all those.
Types of collision:

[!TLDR] (a) Elastic: (ii). (b) Inelastic: (i), (v), (vi). (c) Perfectly inelastic: (iv). (d) Head-on: (iii), (iv), (v). [!ANSWER] …

1. ELASTIC collision -- kinetic energy conserved: only (ii) molecular collisions responsible for gas pressure are treated as elastic in kinetic theory (the idealisation discussed in 4.8.1); everyday macroscopic collisions like a bat-ball or wall-kick always lose some energy.
2. INELASTIC collision -- some KE lost, momentum conserved, bodies do NOT stick together: (i) a ball hit by a bat (some energy lost as sound/heat/ball deformation, ball and bat separate afterwards); (v) kicking a wall out of anger (energy lost as sound/heat/vibration in the foot and wall, foot rebounds); (vi) a carrom striker rebounding off the boundary perpendicular to it (some energy lost on impact, striker rebounds rather than sticking) -- all three lose energy but the colliding bodies separate rather than joining.
3. PERFECTLY INELASTIC collision -- bodies stick together, moving with one common velocity afterwards: (iv) a blob of clay dropped on the ground sticking to it is the textbook example of a perfectly inelastic collision (definition, 4.8.2). …

Apply the definitions of elastic/inelastic/perfectly-inelastic (energy and momentum behaviour, 4.8.1-4.8.2) and head-on (single line of motion, 4.8.3) to each ill …

Assuming each illustration matches only ONE type of collision, when several (like the clay blob, or the wall kick) genuinely satisfy tw …