Question

1. What is the difference between elastic and inelastic collision? 2. Give an example for either one.

Answer 1

1. **Difference between elastic and inelastic collisions:**
- **Elastic Collision**: In an elastic collision, both momentum and kinetic energy are conserved. This means that after the collision, the total energy and total momentum of the system remain the same as they were before the collision. Elastic collisions typically occur between idealized particles or objects, such as billiard balls colliding.

- **Inelastic Collision**: In an inelastic collision, momentum is conserved, but kinetic energy is not. Some of the kinetic energy is transformed into other forms of energy, such as heat, sound, or deformation of the objects involved. A common example of an inelastic collision is a car crash, where the vehicles crumple and lose kinetic energy as they collide.

2. **Example of an elastic collision**: A classic example is the collision between two billiard balls on a pool table. When one ball strikes another at rest, they collide elastically, resulting in both momentum and kinetic energy being conserved during the interaction.

**Example of an inelastic collision**: A real-world example is a football tackle. When a player collides with another player, both players might fall to the ground, and kinetic energy is not conserved, as some energy is transformed into sound, heat, and the deformation of the players' bodies and equipment.