Conservation of momentum and Collision

• The Law of Conservation of Momentum states that the total momentum of two or more objects acting upon each other does not change, provided NO EXTERNAL force acts upon them.
• While the forces are equal in magnitude and opposite in direction, the acceleration of the object is not necessarily equal in magnitude.
• CONSERVATION OF MOMENTUM FORMULA:
• CONSERVATION OF MOMENTUM FORMULA:

  total momentum before = total momentum after

  Pbefore = Pafter

  (m1v1+m2V2) before = (m1v1+m2V2) after
• COLLISIONS:

  Collision is an encounter between two objects resulting in exchange of impulse and momentum

  Because the time of impact is small, it is negligible. The momentum of the system is conserved.
• Kinetic energy may be lost during collisions due to the following:

  1. Converted to heat of any other forms like binding energy, sound, or light.
  2. Spent in producing deformation or damage when objects collide
• ELASTIC COLLISIONS: Momentum and kinetic energy is conserved
• INELASTIC COLLISIONS: Momentum is conserved but not the kinetic energy
• ELASTIC COLLISION: Type of collision in which the total momentum and the total kinetic energy of the system DOES NOT CHANGE, and colliding objects bounce off after collision
• INELASTIC COLLISION:

  Type of collision in which the total momentum DOES NOT CHANGE but the total kinetic energy DECREASES (KEf < KEi) due to the conversion to some other form of energy and colliding objects move separately after collision
• PERFECTLY INELASTIC COLLISION:

  Type of collision in which the objects stick together and move with a common velocity after the collision. Both objects are deformed, and the maximum amount of kinetic energy is lost
• ELASTIC COLLISION:

  • the objects involved remain separate
  • total kinetic energy and momentum are conserved
• PERFECTLY INELASTIC COLLISION:

  • the objects become one mass
  • Kinetic energy is not conserved