It’s that time of year when things start to appear magical, so what better time to get the kids involved in creating a bit of magic of their own.
Our next Exploratorium on Wednesday, Nov 15 at 2:00pm-3:30pm features Magician, Mark Yeager who will do a magic workshop for children in K-5th grades. This is a great opportunity for children to learn some slight of hand and other magical tricks they can do on their own. If they get hooked, let the magic grow by taking a look at our many magic books we have available to be checked out.
Did you realize how many different types of bridges we have in the Quad Cities?
Since designing the Exploratorium Building Bridges program, I keep looking at bridges, explaining to my very patient husband that the footbridge he just crossed over was a beam bridge and the strengths and weaknesses of that type of bridge. All this time I just thought bridges were “pretty” or “ugly” because of their design. I never thought there was a reason for the style of bridge or to really think about the amazing amount of weight these bridges have to carry. It’s been an eye opener.
It all started with the model of the new I-74 bridge that is currently located in our lobby. I thought this would be a great time to do a STEAM program on bridges and how they are built.
At the program we observed what made a design strong with 4 different type of bridges. At the end, everyone designed their own bridge that would be strong enough to hold an apple. If you want to try these at home, they are very simple.
Supplies: 2 even stacks of books, 2 pieces of card stock, scissors, tape and weights. Weights can be anything the same size like small blocks or other toys that are the same size and weight that will not roll away from you or break.
Place a piece of cardstock on the two stacks of books so it looks like a bridge. Now begin adding weights, one at a time. How many weights did you add before the bridge collapsed?
Now create 2 piers from the 2nd sheet of card stock by rolling up the cardstock into a tube and taping it. Cut the tube into 2, sizing them so it fits under the “road” of your bridge. Place the 2 tubes or piers under the bridge and start adding weight again. Did it hold more weight?
Beam bridges are simple to create and are ideal for short distances unless you have other ways to support the bridge.
Supplies: 2 even stacks of books, 2 full pieces of card stock, weights.
Recreate your beam bridge without the piers. Form the second piece of cardstock into an arch and place it under the road of the bridge. How many weights does the bridge hold? Was this more than the beam bridge without piers? With piers?
If you were to create an arch from stones or blocks, this would need tension to hold the arch together. An example of the tension in an arch is to stand facing someone about the same height as you. Both of you hold up your hands and grasp them to form an arch. Now lean forward. The force you feel where your hands meet is the same force that would hold stones together in an arch. The arch shape is able to disperse the weight to the ground or abutment of the bridge.
Supplies: 2 even stacks of books, 1 full piece of card stock, 1 piece of paper, weights.
Truss bridges get their strength from a framework made of triangles. Triangles are much stronger than squares or rectangles because they can move the pressure of the road load from a single point to a much wider area.
Recreate your beam bridge. Remember how many weights it would hold?
Now fold your piece of paper like you would a fan. Spread it out and place it under your road so it spans the bridge. Now try adding weight. Does it hold more?
Why do you think the fanned paper was helpful? Would it work if it were a flat sheet of paper?
Supplies: a long piece of cardboard about 4 ft long for the road. It may be bent. A hole punch, 2 chairs with an open back, pipe cleaners, 2 long pieces of cord about 12-14 ft long and some weights – we used 4 Lego blocks.
I found this bridge fascinating. It seems impossible that two pieces of cord can hold up a bridge!
Place the chairs back to back. Place the strings parallel to each other over the chairs so that the ends go over the front of each chair and reach the floor. If it helps for set up, tape the cords to the top of the chairs. Just be certain to take off the tape when the bridge is assembled. Tie the ends of your string to your weights and pull the weights away from the chairs to make the cords taught. Punch holes on either side of the cardboard, 3-4 on each side, evenly spaced out. You do not need to have holes on the far ends of the cardboard. Attach a pipe cleaner to each hole by threading it through the hole and twisting the end to the pipe cleaner. Place the ends of the cardboard on the seats of the chairs. You may need to support the cardboard until you have the pipe cleaners in place. Next, hook the pipe cleaners onto the cords. Now you can pull the road support away and take off the tape.
Try putting on a toy car on the bridge. Does it hold?
What happens if you move the weights closer to the bridge?
What if you have fewer pipe cleaners? No pipe cleaners?
Can you determine what is supporting the weight?
When I started designing this program, I didn’t know the first thing about bridges, however, through the books and kits we have at the library plus the Internet, I developed a great respect for the bridges I see every day. Which is a lot of bridges!
It turns out the Quad Cities has many examples of the different types of bridges. When you cross a bridge, see if you can determine what kind it is: Beam, Arch – Tied Arch, Suspension, Truss, Swing, or Cable-Stayed.
And the next time you come into the library, be certain to check out the new I-74 bridge model in the lobby. It’s awesome!
Join us October 18th from 2 to 3:30 for CSI Exploratorium! For those who don’t know, Exploratorium is a weekly program for kindergarten to fifth graders where we cover all things STEAM (Science, Technology, Engineering, Art, and Math). We usually do this program as a drop in, where you can come anytime from 2 to 3:30 BUT we are changing that a bit for CSI Exploratorium. The program will be from 2 to 3:30 but it will NOT be a drop in. Make sure you are here at 2pm to join in the fun as real detectives and techs from the Moline Police Department will be here to guide us through some very exciting parts of their job! Want details about this and other programs? Click here for our calendar!
Spread the word! Exploratorium is about to restart for the school year. What is Exploratorium? It’s a chance to try your hand at something new each week. It might be messy, it might be creative, it might be scientific, or it might be something totally bizarre. You can check at the Children’s Desk to find out each topic during the month. On Wednesday, September 13 we will kick-off the series with the Science of Spin. The Grout Museum will be at our library to put a new spin on art using whirly-gigs, gyroscopes and tops to create spin art and color wheels. It’s a fun-filled program that will have everyone spinning science and art so fast you might get dizzy!
You don’t need to register for this free program. Just stop on by the children’s program room between 2:00pm-3:30pm for the fun.
See you there!
About The Grout Museum District and the Carl A. and Peggy J. Bluedorn Science Imaginarium:
The Grout Museum of History and Science features permanent and continually changing exhibitions of area history, regional flora and fauna, and the only public planetarium in Northeast Iowa, which holds weekly shows.
Science comes alive at the Carl A. and Peggy J. Bluedorn Science Imaginarium, a three-floor, interactive science center. Here, hands-on exhibits show how science affects your everyday life. Science Demonstrations get you even more involved in the action, and show you how exciting science can be.