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1R40.30 - Balls Wanted Dead or Alive

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​1R40.30 - Balls Wanted Dead or Alive

Title1R40.30 - Balls Wanted Dead or Alive

Demonstrate elastic and inelastic collisions.

Assembly Instructions

Provide both balls and a container. Two different sizes are available, 1 1/4" in diameter (Lecture Hall use) and 3/4" in diameter (export).

Setup Time5
Operation Time5
Preview Time5
Operation Instructions

Two balls which have the same size, color, and density are dropped from the same height onto a hard surface (pick an arbitrary but repeatable height). One bounces to almost the same height while the other doesn't bounce.

Demo on DimeNo
PIRA 200Yes
Export Instructions (if different)

The balls have very similar aesthetic properties: size, color, and density. They have one important difference: elasticity.

In an elastic collision, the kinetic energy is not converted into heat. In an inelastic collision, the kinetic energy is converted into heat.

What it looks like If heat is created: the ball doesn't bounce back off a hard surface. If little heat is created: the ball bounces back with almost equal height.

Category1 Mechanics
Subcategory1R - Properties of Matter
Keywordshappy unhappy balls, happy sad balls, bounce no bounce balls, dead and live balls, bounce-no-bounce balls, happy-sad balls, happy-unhappy balls, dead-live balls
Construction Information
dead/alive ball sets