Published: 2014-10-06 10:08 |

Category: Science | Tags: teaching

I’m on bath duty each night. After dinner, the water runs, and Meredith gets really, really excited. The tub is full of boat, plastic chains, and foam letters which have a great feature of sticking to the wall when they’re wet. I’ve even discovered that, if thrown just right, they will stick on their own.

I don’t want to humblebrag, but I can get it to stick one out of seven attempts.

I managed to get a “G” to stick tonight and I started wondering why it stuck to the wall…is it cohesion or adhesion?

I’m still thinking through how to best explain this…which force is more prevalent? Is is one more powerful than the others?

When I taught adhesion and cohesion, never considered a problem like this…they were all straight forward because I had to assess the standard. I was afraid of confusing them. Now, I’m more afraid of what I missed because I didn’t confuse them.

How would you explain the picture? What would your students say?

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