Elastic and Inelastic Collisions

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In physics, collisions can be classified as either elastic or inelastic based on the conservation of momentum and kinetic energy.

In all types of collisions, momentum is conserved. This means that the total momentum before the collision is equal to the total momentum after the collision.
Mathematically, this is expressed as: Σp_initial = Σp_final, where Σp represents the total momentum.

In elastic collisions, not only is momentum conserved, but kinetic energy is also conserved. This means that the total kinetic energy before the collision is equal to the total kinetic energy after the collision.
Elastic collisions are characterised by the fact that no kinetic energy is lost during the collision.
Interactions between molecules are examples of perfectly elastic collisions.
In perfectly elastic collisions, objects bounce off each other without any loss of energy.

In inelastic collisions, momentum is still conserved, but kinetic energy is not conserved. This means that the total kinetic energy before the collision may not be equal to the total kinetic energy after the collision.
In most real-world scenarios, such as collisions involving snooker balls, some kinetic energy is lost due to various factors like friction and deformation.
In inelastic collisions, kinetic energy is transformed into other forms of energy, such as heat or sound.

Physics

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Calculations in Collisions

When working with collisions, it's essential to calculate the kinetic energy for each object both before and after the collision.
Kinetic energy can be calculated using the formula: KE = ½mv², where KE is kinetic energy, m is mass, and v is velocity.
To determine whether a collision is elastic or inelastic, compare the total kinetic energy before and after the collision.
If the kinetic energy before and after is the same, it's an elastic collision. If not, it's an inelastic collision.

Diagram 2

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In elastic collisions, both momentum and kinetic energy are conserved, and no energy is lost during the collision.
In inelastic collisions, momentum is conserved, but kinetic energy is not, and some energy is converted to other forms.
Real-world collisions, like those involving everyday objects, are typically inelastic due to energy losses from factors like friction and deformation.
To determine the type of collision, compare the total kinetic energy before and after the collision. If they are equal, it's elastic; if not, it's inelastic.