Inelastic Collisions

Definition

An inelastic collision is a type of collision where the colliding objects stick together after the impact, resulting in a change in their kinetic energy. In this type of collision, the total momentum is conserved, but the total kinetic energy is not conserved due to the loss of energy in the form of heat, sound, or other forms of energy.

5 Must Know Facts For Your Next Test

1. In an inelastic collision, the colliding objects stick together, resulting in a change in their kinetic energy.
2. The total momentum is conserved in an inelastic collision, but the total kinetic energy is not conserved due to the loss of energy in the form of heat, sound, or other forms of energy.
3. Inelastic collisions are often used to measure the coefficient of restitution, which is a measure of the energy lost during the collision.
4. Inelastic collisions can be classified as either perfectly inelastic, where the objects stick together completely, or partially inelastic, where the objects separate after the collision.
5. Inelastic collisions are commonly observed in everyday life, such as when a ball bounces on a surface or when a car collides with another object.

Review Questions

• Explain how the conservation of momentum is applied in an inelastic collision.
  • In an inelastic collision, the total momentum of the colliding objects is conserved, meaning that the initial momentum of the objects before the collision is equal to the final momentum of the combined objects after the collision. This is because momentum is a vector quantity, and the total momentum of the system must be conserved, even though the kinetic energy is not conserved due to the loss of energy in the form of heat, sound, or other forms of energy.
• Describe how the coefficient of restitution is used to measure the energy lost in an inelastic collision.
  • The coefficient of restitution is a measure of the energy lost during an inelastic collision. It is defined as the ratio of the relative velocity of the objects after the collision to the relative velocity of the objects before the collision. The coefficient of restitution ranges from 0 to 1, with 0 representing a perfectly inelastic collision where all the kinetic energy is lost, and 1 representing a perfectly elastic collision where no kinetic energy is lost. By measuring the coefficient of restitution, the amount of energy lost in an inelastic collision can be determined.
• Analyze the differences between elastic and inelastic collisions in the context of $\text{kinetic energy}$ and $\text{momentum}$ conservation.
  • In an elastic collision, both the kinetic energy and momentum of the colliding objects are conserved. This means that the total kinetic energy of the objects before the collision is equal to the total kinetic energy of the objects after the collision, and the total momentum of the objects before the collision is equal to the total momentum of the objects after the collision. In contrast, in an inelastic collision, the total momentum is conserved, but the total kinetic energy is not conserved due to the loss of energy in the form of heat, sound, or other forms of energy. This means that the kinetic energy of the objects after the collision is less than the kinetic energy of the objects before the collision, while the total momentum remains the same.

Related terms

Elastic Collisions: Elastic collisions are a type of collision where the colliding objects bounce off each other, and the total kinetic energy is conserved.

Momentum: Momentum is the product of an object's mass and its velocity, and it is a vector quantity, meaning it has both magnitude and direction.

Kinetic Energy: Kinetic energy is the energy an object possesses due to its motion, and it is directly proportional to the object's mass and the square of its velocity.