Question

1)What is energy? Is it conserved, and how is this conservation different than momentum?

2) What is the difference between a closed system and an isolated system?

3) What is the difference between elastic, inelastic, totally inelastic, and super-elastic collision?

4) What is Mazur's notation for relative velocity and what is relative velocity anyway?

Answer 1

1) Energy is defined as the , it is the ability to do workt. energy is conserved, ie energy neither be created nor be destroyed.

The conservation of momentum is valid for almost every where without the presense of an external impact force or for an isolated system. in some certain system like collission between particles, where momentum is conserved while eneryg not.

2) in a closed system there must be energy exchange between the system and surrounding but not the matterer. whereas in an isolated system neither energy nor matter would excchange with the surrounding.

3)in elasitic collision both kinetic eneryg and momentum would conserve whereas in inelastic collision kinetic energy is not conserved while momentum is conserved.

in a tottaly inelastic collission the kinetic eneryg of the colliding particle completely lost and beocome zero after collission.

in super-elastic collision, there must be increase in the kinetic energy of the system after collision and this is noted very rarely.

4)The relative velocity of an object A with respect to B is given by

Relative velocity is defined as , it is the velocity of an object or body with respect to other body.