Customers most agreed on the following attributes:
Comments about Arbor Scientific Happy/Unhappy Balls:
I love this demo! My students are really surprised when they take two apparently identical (well, nearly) balls and bounce them on the table. One bounces normally, the other hits the table and dies. They hypothesize all kinds of reasons why this might be the case, and they are intrigued that the only difference is the rubber material.
I used these balls to demonstrate the contrast of elastic and inelastic collisions when discussing momentum conservation. I have also used them in chemistry in the context of the relationship of physical properties to molecular structure, though I can only present this idea in general terms.
The balls come with a data sheet that describes the energy absorbing rubber that comprises the unhappy ball.
Worth the money, and I think that Arbor has the best price that you will find for happy/unhappy balls.
Comments about Arbor Scientific Happy/Unhappy Balls:
They are easy to use and effective. The information in the sheet page is very accurate and one of the best I've ever seen. I wish they were bigger
Comments about Arbor Scientific Happy/Unhappy Balls:
They bounce and roll differently but they also don't look the same. One is shiny and one is matte. Kids note the difference right away so they don't expect the same behavior.
Comments about Arbor Scientific Happy/Unhappy Balls:
Great to teach about energy transformation as well as chemical and physical properties of materials.
Comments about Arbor Scientific Happy/Unhappy Balls:
This product can be used to demonstrate efficiency, begin a disucussion on coefficient of restitution or impulse equals change in momentum. Pull these little guys out when you want to get your students' attention!
Comments about Arbor Scientific Happy/Unhappy Balls:
I purchased a class set of these balls and give them to the students with a piece of wood when I introduce momentum and impulse. I tell them they are sitting on their bed when the house catches fire and they need to design and complete an experiment to determine which ball will be more effective at closing their bedroom door to allow them time to escape out their window.
Comments about Arbor Scientific Happy/Unhappy Balls:
I was glad to finally find these happy/ sad balls for a good price. I used them in church to explain why we can't judge people by the way they look. The kids and adults were enthused by them.
Comments about Arbor Scientific Happy/Unhappy Balls:
we use these in our sales training.
Comments about Arbor Scientific Happy/Unhappy Balls:
It's a really fun product just to have and watch. Great for magic tricks and the like.
Comments about Arbor Scientific Happy/Unhappy Balls:
Demo of elastic and inelastic collusions.
Comments about Arbor Scientific Happy/Unhappy Balls:
Great demonstration of material characteristics
Comments about Arbor Scientific Happy/Unhappy Balls:
An excellent learning tool.
[1 of 1 customers found this review helpful]
Comments about Arbor Scientific Happy/Unhappy Balls:
Met expectations.
Comments about Arbor Scientific Happy/Unhappy Balls:
Try chilling the balls in icewater for a while. The unhappy ball will bounce, the happy ball won't. Dramatic. (The response of the materials to temperatures is not linear.)
It is interesting to ask the students where the "lost" energy goes when the ball does not bounce. Does the earth move?
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[6 of 7 customers found this review helpful]
Comments about Arbor Scientific Happy/Unhappy Balls:
For such a simple item, I have been continually surprised how much people like these. I usually bounce the superball for them, palm it and give them the dud, asking them to do the same. When it stops dead on the floor -- without a single bounce -- the look on their face is utter confusion. Provides a useful point for discussion of elasticity, polymers etc. What are these materials useful for? If the sad ball didn't bounce, where did the energy go? And so on. BTW, this is a very good price.