It’s high time I posted about fun science at home! I’ve got two experiments outlined below. I admit that it was difficult to come inside. The weather and fall colors are gorgeous.
Along with fall comes the inevitable raking. Good thing I have Louie to help! And boys to bribe.
These experiments have minimal supplies, so you won’t even need to to to the store first! Especially if you’ve got as many drawers of junk as I do. (which I also ignore!)
The experiments will make great practical jokes.
Junk Drawer! Science At Home
In fact, I bet if you rummage around in your junk drawer, you’ll find what you need! These STEM science at home experiments will cost zero dollars! And they’re fun.
You’ll look like an expert because I’m explaining the ‘why’ behind the science.
Time to impress your posse with science at home!
Experiment # 1 : Spinning Straws
Spin a straw with no hands!
Supplies that I bet you have in your junk drawer!
Steps to Spinning Straw Science Experiment
Video of Spinning Straws
The Science Behind Spinning Straws
Two words : Static Electricity
Static electricity is the build-up of an electrical charge on the surface of an object. The reason that it’s called static electricity is because the charges stay in one area for some time. They don’t flow or move to a different area.
What are charges, exactly? Electrons!
When you rub the straw on your head –or against Louie’s hair– the electrons jump! Both straws gain electrons from your hair!
Since both straws have extra electrons, they are both negatively charged. Like charges repel each other. Hence one straw pushes the other away.
This science experiment at home is demonstrating the repelling of like charges!
There are many ways to make electrons jump.
Rubbing your feet across a carpet causes the electrons to jump onto you. More and more join your trek across the carpet.
Eventually more electrons don’t want to come up on you because you’re so charged up. You end up with a high voltage, about 20,000 to 25,000 volts.
That’s serious power at your fingertips, considering a normal electrical outlet on the wall is only around 100 volts of electricity.
And bolt they do. You touch the more positively charged doorknob–after all you are full up with electrons– and get a shock!
Static electricity works best on cold, dry days. This is why we get more shocks in winter. If it’s humid, the way it is in the summer, there is more water vapor in the air.
Water molecules are polar, meaning they have a positive and negative side. On a humid day, the electrons from the carpet will jump to the positive side of the water molecules in the air, instead of to you.
Fun Experiment # 2: Do Not Open or The Water Bottle Trick
Who doesn’t love a challenge? The second someone tells me NOT to do something, I’m tempted. I shouldn’t call science a trick, but with this one, you can trick your kids, guests, siblings, anyone you please. With science at home! Time to trick your posse….
Supplies that I bet you have in your junk drawer or in this case, the recycling bin!
Steps for Water Bottle Trick
Video of Water Bottle Trick
The Science Behind the Water Bottle Trick
When you pour water into the bottle, the molecules of air that once occupied the bottle come rushing out of the top. You don’t notice this because molecules of air are invisible.
Likewise, when you pour water out of a bottle (thanks to gravity) the water rushes out. The other action that’s occurring is that air rushing into the bottle.
Think of it as an even exchange of water for air.
When the lid is uncapped, air sneaks in through the top of the bottle. The air pushes down on the water (along with some help from the force of gravity), and the water squirts through the holes in the bottle.
This makes a great practical joke for kids. They’re learning science and having fun.
You might ask why poking a tiny hole in the side of a bottle would not cause it to leak. It would if air molecules can sneak into the bottle. However, when the lid is on the bottle, air pressure can’t get into the bottle to push on the surface of the water.
The water molecules work together to form a kind of skin to seal the holes—it’s called surface tension. (I talk about this in that other post, too)
Surface tension occurs because water molecules are attracted to each other! Remember that water molecules are polar, meaning they have a positive and negative side. Opposite charges attract!
This is called cohesion. (the intermolecular attraction between like-molecules)
Water really is amazing!
Some insects use surface tension to stay afloat! They are lightweight enough so they don’t disrupt cohesion. (Larger animals incorporate other adaptations to help them stay on top of the water surface)
I bring a water bottle along on walks with Louie and untape the hole so he can have a little drink. The tape is necessary in this case, because if I grab the bottle, exerting pressure on the side of the bottle will force water out of that hole.
This science trick is portable!
And there we go! Science at home with 2 fun experiments. Go ahead, trick your friends!
Let me know if you try either of these science experiments at home !
Louie vastly preferred the water bottle experiment to the spinning straws experiment.
Which experiment do you like best?