8 Difference Between Elastic And Inelastic Collision

What Is Elastic Collision?

Elastic collision is a type of collision in which the total kinetic energy is conserved. What this means is that, the total kinetic energy of the colliding bodies after collision is equal to their kinetic energy before collision. In a perfectly elastic collision, there is no net conversion of kinetic energy into other forms such as heat, noise or mechanical energy.

During collision of small objects, kinetic energy is first converted to potential energy associated with a repulsive force between the particles, and then this potential energy is converted back to Kinetic energy. Examples of elastic collision include: collision in ideal gases, collision of atoms, neutron-nucleus scattering reaction, and collision of billiard balls etc.

What You Need To Know About Elastic Collision

  1. Elastic collision is whereby two colliding objects do not stick together; they bounce back without undergoing any deformation or heat generation.
  2. In elastic collision, the momentum and total kinetic energy before and after collision is same.
  3. The forces involved during elastic collision are conservative.
  4. A good example of elastic collision is the swinging balls, collision of atoms.
  5. In elastic collision, mechanical energy is not transformed into other energies such as sound energy or thermal energy.
  6. Linear momentum is conserved.
  7. Kinetic energy is conserved.
  8. During collision of small objects, kinetic energy is first converted to potential energy then, potential energy is converted back to kinetic energy.

What Is Inelastic Collision?

Inelastic collision is a type of collision in which the total kinetic energy is not conserved due to the action of internal friction. What this means is that, the total kinetic energy of the colliding bodies after collision is not equal to their kinetic energy before collision. In perfect inelastic collision, there is net conversion of kinetic energy into other forms.  In this type of collision, energy is lost to the environment, colliding objects are deformed; heat and noise is generated.

Unlike elastic collision, inelastic collisions they don’t conserve energy, but they do conserve momentum. When two bodies collide, the equal and opposite impulsive forces are internal forces in what is referred to as a two-body system and consequently have no effect on the total momentum of the system. This condition means that the sum of the momentum of the bodies before impact is equal to the sum momentum after impact.

What You Need To Know About Inelastic Collision

  1. Inelastic collision is a kind of collision whereby the two colliding objects stick together and move with the same post-collision speed. In this type of collision colliding objects are deformed and heat is generated.
  2. In inelastic collision, the momentum and total kinetic energy before and after collision is not same.
  3. The forces involved during inelastic collision are non-conservative.
  4. A good example of inelastic collision is an automobile collision.
  5. In inelastic collision, mechanical energy is transformed into other forms of energy such as sound energy and thermal energy.
  6. Linear momentum is conserved.
  7. Kinetic energy is not conserved due to action of internal friction.
  8. During inelastic collision some kinetic energy is turned into vibrational energy of the atoms, causing a heating effect and bodies get deformed.

Elastic Vs Inelastic Collision In Tabular Form  

BASIS OF COMPARISON   ELASTIC COLLISION INELASTIC COLLISION
Description Elastic collision is whereby two colliding objects do not stick together; they bounce back without undergoing any deformation or heat generation.   Inelastic collision is a kind of collision whereby the two colliding objects stick together and move with the same post-collision speed. In this type of collision colliding objects are deformed and heat is generated.  
Momentum And Total Kinetic Energy The momentum and total kinetic energy before and after collision is same.   The momentum and total kinetic energy before and after collision is not same.  
Forces Involved The forces involved during elastic collision are conservative.   The forces involved during inelastic collision are non-conservative.  
Example A good example of elastic collision is the swinging balls, collision of atoms.   A good example of inelastic collision is an automobile collision.  
Mechanical Energy  Mechanical energy is not transformed into other energies such as sound energy or thermal energy.   Mechanical energy is transformed into other forms of energy such as sound energy and thermal energy.
Linear Momentum Linear momentum is conserved.   Linear momentum is conserved.  
Kinetic Energy Kinetic energy is conserved.   Kinetic energy is not conserved due to action of internal friction.  
Kinetic Energy Conversion During collision of small objects, kinetic energy is first converted to potential energy then, potential energy is converted back to kinetic energy.   During inelastic collision some kinetic energy is turned into vibrational energy of the atoms, causing a heating effect and bodies get deformed.