THIS IS SCIENCE: Experiments you can do at home with your kids
Goo (or non-Newtonian fluid)
For this month's This is Science, we went to the Chicago Children's Museum, where Laura Wurzburger and Chelsie Burdine helped me make goo.
As with all good experiments, we ran into a snag. The two parts glue and one part starch did not come together quickly enough. Perhaps it was the way I was doing it - squishing it through my fingers rather than kneading it with my palms - or perhaps it was something in the air making things moister. We ended up having to add a little glue. The opposite can also happen - you may need to add starch if it's too thick.
The bottom line is, don't worry if it's not going exactly as you think it should. Stand back and reassess, and you will be fine.
It would also be great if you could share your experience by commenting below, or videotaping yourself and your child(ren) making the goo. We will post it online.
The goo we make, as Laura points out, is not liquid and it's not solid, but it sort of has the properties of both. The proper name is Non-Newtonian Fluid, and we are surrounded by them in our everyday lives.
Not all non-Newtonian fluids act in the same way, and often act differently depending on whether they're moving. You can test this with your goo by constantly moving it with your hands. Observe how it acts like a solid, not losing its shape. Then just stop moving your hands. Observe how quickly the goo seems to melt and lose its shape.
Unlike water, you can walk on non-Newtonian fluids. But don't stop, or you will sink fast. These guys filled a pool with a mix of cornstarch and water (sometimes called Oobleck - from a Dr. Seuss book) and show clearly how motion keeps them up and stillness makes them sink.
Non-Newtonian Scavenger Hunt
There are lots of non-Newtonian fluids in your house. Some are more runny than others, but they all have uneven flow when poured. A great way to teach your kids to identify non-Newtonian fluids is to have a scavenger hunt. Here are some clues you can use:
This red substance makes everything good to eat.
Pour it on fries or hot dogs, or broccoli for a treat.
Pour this on pancakes, but don't get picky.
If you stick your fingers in it, you will get sticky.
Too much sugar and you'll have to brush out.
This minty stuff will make your mouth happy, no doubt.
Fingers and brushes turn this into art.
Tell mommy you love her, and make a big heart.
For milk that is chocolatey, or eating ice cream,
this topping makes dessert a sweet dream.
This squishes your hair up into all sorts of things.
Make it look like a crown and pretend you're a king.
But be careful of dripping, or your eyes will sting.
Other non-Newtonian household fluids are:
- custard or pudding
- caramel topping (as opposed to the chocolate from the rhymes above)
- liquid soap
You can also bake some bread with your child. That dough is definitely a non-Newtonian fluid.
Of course, you can buy non-Newtonian fluids like Silly Putty or Play-doh, but it's more fun to make it at home.
And, to distract your child from the pain, the next time he or she gets a cut, explain as you're putting on the bandaid that blood is also a non-Newtonian fluid.
Here's a really great website that explains both Newtonian and non-Newtonian fluids.
(Answers to rhymes: ketchup, syrup, toothpaste, paint, chocolate syrup or sauce, shampoo.)
For the month of April, This is Science is turning flowers different colors - just like when your tongue turns purple when you drink grape juice. It's simple chemistry, in which molecules that are alike follow one another up the stem of the flower, like liquid in a straw. Try it at home and see what colors you can make.
Making simple sound effects and musical instruments
This month on This is Science!: Make simple sound effects or musical instruments. Perfect for rainy days and little kids. Good for older kids' first science project. Experiment and play! Thanks to the beautiful Children's Museum in Oak Lawn for their hospitality and ideas.
Egg drop inertia experiment at Museum of Science and Industry
This is Science! ChicagoParent.com's new video series in which we do a science experiment or demonstration that you can do at home. This month, we start with the Museum of Science and Industry, where we make eggs drop into a glass of water. This experiment is primarily testing Newton's First Law of Motion, which is, "An object in motion tends to stay in motion, while an object at rest tends to stay at rest." (OK, since there was a force used to move the eggs, we were testing out the Second Law of Motion a bit, too.)