All systems lie on smooth horizontal surfaces. Match each case with centre-of-mass/momentum/energy behaviour.

List 1

1. (A) Blocks have initial velocities while spring is relaxed

   

2. (B) Constant external force on one block of a spring system

   

3. (C) Man walks on a large plank at constant velocity

   

4. (D) Man jumps between two trolleys with relative speed 4 m s⁻¹

   

5. (E) .

List 2

1. (P) COM will not move horizontally

2. (Q) COM will move horizontally

3. (R) Mechanical energy conserved

4. (S) Mechanical energy increases

5. (T) Linear momentum of complete system always remains constant