Elastic and Inelastic Collisions

Front

Momentum Noun

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[moh-men-tuhm]

Back

Momentum

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A physical quantity describing an object's quantity of motion, defined as the product of its mass and velocity.

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Example: A bowling ball and a baseball moving at the same speed have different momenta because of their different masses, resulting in a much greater impact from the heavier ball.

Front

Impulse Noun

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[im-puls]

Back

Impulse

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The change in momentum of an object, calculated as the product of the force applied and the time duration.

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Example: This diagram shows that impulse involves a force acting over time. When a ball bounces off a wall quickly (less time of contact), it experiences a large force of impact.

Front

Vector Quantity Noun

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[vek-ter kwon-ti-tee]

Back

Vector Quantity

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A physical quantity that is fully described by both a magnitude, which indicates its size, and a specific direction.

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Example: This diagram shows how to add two vector quantities. The tail of vector B is placed at the head of vector A, and the resulting vector C is drawn from the start of A to the end of B.

Front

Isolated System Noun

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[ahy-suh-ley-tid sis-tuhm]

Back

Isolated System

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A system on which no net external forces act, allowing for the conservation of the system's total momentum.

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Example: An isolated system is a container where nothing gets in or out; neither matter nor energy (like heat) can be exchanged with the surroundings.

Front

Collision Noun

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[kuh-lizh-uhn]

Back

Collision

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An event where two or more bodies exert forces on each other for a short time, causing an exchange of impulse.

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Example: This diagram shows two objects with mass (m) and velocity (v) before and after they collide, illustrating the fundamental components of a collision.

Front

Kinetic Energy Noun

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[ki-net-ik en-er-jee]

Back

Kinetic Energy

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The form of energy that an object possesses due to its motion, dependent on its mass and velocity.

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Example: A foot kicks a soccer ball, a type of collision that gives the ball kinetic energy. The moving ball possesses kinetic energy, the energy of motion.

Front

Elastic Collision Noun

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[ih-las-tik kuh-lizh-uhn]

Back

Elastic Collision

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A collision in which there is no net loss of kinetic energy, meaning both momentum and kinetic energy are conserved.

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Example: This diagram shows two objects with mass (m) and velocity (v) colliding and bouncing off each other, which is characteristic of an elastic collision.

Front

Inelastic Collision Noun

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[in-ih-las-tik kuh-lizh-uhn]

Back

Inelastic Collision

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A collision where kinetic energy is lost and converted into other forms, although the total momentum remains conserved.

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Example: This diagram shows a projectile hitting and sticking to a hanging block, causing them to swing up together, which is an example of an inelastic collision.

Front

Perfectly Inelastic Collision Noun

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[pur-fekt-lee in-ih-las-tik kuh-lizh-uhn]

Back

Perfectly Inelastic Collision

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A collision where the maximum amount of kinetic energy is lost and the colliding objects stick together after impact.

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Example: A moving hockey puck collides with a stationary goalie, and they stick together, moving as one object, which demonstrates a perfectly inelastic collision.

Front

Conservation of Momentum Noun

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[kon-ser-vey-shuhn of moh-men-tuhm]

Back

Conservation of Momentum

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The principle stating that the total momentum of an isolated system remains constant before and after any interaction or collision.

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Example: This diagram shows that in a collision, the total momentum of two objects before they collide (left) is equal to their total momentum after they collide (right).