 Hi, welcome to the MIX, the teen center at the San Francisco Public Library. My name is Ileana and I am your humble host for our STEM Challenge Yourself series where our remarkable librarians come up with science experiments that you can try at home. In today's challenge you're going to learn a little bit about static electricity and the powers of observation with everyday items. So I think you're ready for the challenge. Take it away. Hello friends, I'm Mr. Joseph. You might remember me from previous STEM challenges or during class visits. I'm super ecstatic to guide you on how to make electricity. Alright, so what do we need for this experiment? We need our precious library card, two balloons and make sure they have strings on them and paper that's been shredded into tiny pieces, foam balls, tiny foam balls, make sure you put them in a clear plastic cup, also foam balls in a ziplock bag. And finally the most important part is a fabric that's made out of wool. If you don't have a fabric that's made out of wool, you can also use your hair. So now that we have our materials, let's get started. Let's generate electricity by rubbing this library card onto the wool fabric. And you want to make sure you rub it about 30 times, on 345679, I think that's 30. What do you think? Okay, before I place my library card on our first testing material, the paper, what do you think will happen? So let's find out, oh right, so we have a magnetic effect. The static electricity on the library card attracts the papers to cling on and stick on the card. That's so cool. Okay, let's try our next material, which are foam balls in a cup, again so we need to rub it about 30 times. And this time I'm going to insert my library card on the foam balls and look at that. Look at all those foam balls attracted to the library card, it's a magnetic effect. All right, and let me try to get them out there, okay, for the next material, foam balls inside a ziplock bag. So we're going to hover and slide the library card and you can see them moving around and jumping around inside the bag. How cool is that? So what is happening and why, how does electricity form on our library card when we rub it on the wool? All around us, my hair, this paper, this foam balls, the balloons, this fabric, this library card made up tiny particles called atoms. And atom is a building block, all matters in the universe. And we have an illustration here of an atom and circling and whizzing around the center of an atom are even tiny particles called electrons. Electrons are extremely electrically supercharged and sometimes they move to another atom. And that's exactly what's happening is the electrons from the fabric, from our hair, escape and move to our library card. Thus, our library card is now electrically charged with electrons. So let's play, let's do another experiment with electrons. And this time we're going to use different materials. We're going to use a balloon and make sure your balloons have a string on them. And so we have our paper, our foam balls in a cup. And we don't need this foam, this foam balls in a bag. And I'm just going to place this balloon right here. We're going to test this balloon and where I will use this balloon instead of a library card. And also, I have an extra foam balls here that are different colors. This one is a blue color and this one is red. Okay, so we are ready to test these materials. So let's transfer some electrons onto this balloon by rubbing. Okay, did you see that? Sometimes you can hear static electricity. And let's see what happens. Whoa! Actually, we grabbed everything here. So as you can see, the papers are attracted to the balloon and the foam balls as well. So we just get that magnetic effect. Whoa! And here's the coolest thing, okay? Watch carefully, watch my finger and you can see they're trying to get away from my finger. I can move those balls with just hovering my finger. Let me get this out, this paper, okay? So again, we get this magnetic effect. The objects are attracted to the static electricity we developed onto our library card. Okay, and I'm going to move this paper, we're done with the foam balls. Now we have these different foam balls, okay? So let me just try to remove those foam balls away, generate more electrons on this balloon. Okay, and I'm going to hold it up so you can see. This time they're trying to get away from the balloon. They're moving away from the balloon and that's called repel, okay? And so we're going to do another experiment with another balloon. So we have, let me put this one right here. So let me generate some electrons on this balloon. I'm going to tie it onto the table here so it doesn't escape. It's trying to follow me. I think I've generated enough electricity on myself that they're trying to cling on to me. Okay, and let's see what happens. First, they're trying to attach to myself but they're also repelling from each other. How close that? Static electricity is so much fun. And so, so far we've witnessed two electrical force. We've witnessed the electrical force called a track where two objects come together, the papers are attracted to the balloon and repel where the blue foam balls somehow repel from the balloon. Cool is that? Static electricity is so much fun. It's full of magic. You can explore all materials around your home and come up with the same electrical force. But not only it's fun, it also plays an important role in our society. Thanks to this awesome Asian American named Peter Tsai, we'll supercharge our N95 mask so that we can better protect it from tiny particles including viruses. That's awesome invention. Have a happy experiment and hope to see you again. Bye and back to Eliana. Wow, Joseph, that was electrifying. Thanks so much for sharing how you can experiment with household items to learn more about static electricity. And I appreciate you noting Asian American inventor Peter Tsai with his role in COVID-19. So keep experimenting. Be sure to check out sfpl.org slash STEM challenge for resource lists and stay STEM-tastic.