Name: central and oblique collision dynamics
Uploaded: 2024-03-07T13:22:20.000Z
Duration: 1 min 30 s
Channel: JoVE

Impacts can be classified into various types.
A central impact occurs when two objects collide head-on with opposite velocities aligned along the line of impact.
Oblique impact occurs when two objects collide at an angle, causing a change in direction and velocity.
The ratio of the relative velocity after and before the impact is the coefficient of restitution. It measures the elasticity of a collision and ranges from zero to one.
Factors like impact velocity, size, and shape of the colliding bodies affect the coefficient of restitution.
A perfectly elastic impact occurs when the coefficient of restitution is one, and there is no loss of kinetic energy. However, achieving perfect elasticity is impossible. During the collision, a part of kinetic energy is always lost in some form.
When the coefficient of restitution is zero, the impact is called a plastic impact, wherein the colliding particles stick together and move with a common velocity after the collision.
The coefficient of restitution determines the bounciness of an object. Higher values indicate a greater bounce-back with the original speed.

types of impact

Types of Impact

Impacts can be classified in various forms, primarily under two subgroups: central impact and oblique impact. A central impact occurs when two objects collide head-on, possessing opposite velocities aligned along the line of impact. Conversely, an oblique impact occurs when two objects collide at an angle, resulting in a modification of both direction and velocity.
The coefficient of restitution is a metric for understanding the dynamics of impacts. It quantifies the ratio of relative velocity after the impact to that before the impact, reflecting the elasticity of the collision. This coefficient ranges from zero to one, with a value of one indicating a perfectly elastic impact where no kinetic energy is lost. However, achieving absolute elasticity is unattainable, as some kinetic energy is inevitably dissipated during the collision.
Several factors influence the coefficient of restitution, including impact velocity, as well as the size and shape of the colliding bodies. When the coefficient is zero, the impact is termed a plastic impact, where colliding particles adhere together and move with a shared velocity post-collision. The coefficient of restitution essentially determines the bounce-back behavior of an object, with higher values indicating a more pronounced rebound to the original speed. In practical terms, a perfectly elastic impact remains an idealized scenario, while the coefficient of restitution serves as a pivotal parameter in gauging the impact&#39;s bounciness.

Impacts can be classified into various types.
A central impact occurs when two objects collide head-on with opposite velocities aligned along the line of ...

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JoVE Core

Mechanical Engineering

Unit 1

Kinetics of a Particle: Impulse and Momentum

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KEY TERMS AND CONCEPTS

central and oblique collision dynamics

Impact events are described by how two objects collide and how they move after the collision. The two main forms are central impact and oblique impact. A central impact happens when objects strike head-on, with opposite velocities along the line of impact.

An oblique impact happens when objects collide at an angle. In this case, both direction and velocity can change after the collision. This makes the motion after impact more complex than in a head-on collision.

The coefficient of restitution helps measure how elastic an impact is. It is the ratio of relative velocity after impact to relative velocity before impact. The value ranges from zero to one, and a value of one represents a perfectly elastic impact with no kinetic energy loss.

A perfectly elastic impact is only an ideal case, because some kinetic energy is always dissipated during a real collision. The coefficient of restitution is affected by impact velocity and by the size and shape of the colliding bodies. When the coefficient is zero, the collision is called a plastic impact, and the particles stick together and move with the same velocity after impact. In practice, this coefficient shows how much an object bounces back, with higher values giving a stronger rebound.

Central and Oblique Collision Dynamics

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Impact events are described by how two objects collide and how they move after the collision. The two main forms are central impact and oblique impact. A central impact happens when objects strike head-on, with opposite velocities along the line of impact. An oblique impact happens when objects collide at an angle. In this case, both direction and velocity can change after the collision. This makes the motion after impact more complex than in a head-on collision. The coefficient of...

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key terms and concepts

Learn how central and oblique impacts differ, and how the coefficient of restitution shows whether a collision is elastic, plastic, or somewhere in between.

Central and Oblique Collision Dynamics | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

Central and Oblique Collision Dynamics

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