1Scan this QR code Visit Homeschool-101.com

2

RECEIVE 2 FREE E-BOOKSWHEN YOU JOIN THOUSANDS OF OTHER

HOMESCHOOL FAMILIES AT HOMESCHOOL-101.COM!

2 Ways to Quickly Join

DON’T MISSREASONSTO JOIN5

Thousands of Other Homeschoolersin the Homeschool-101.com

Community!

2 FREE e-Books when you sign up

FREE weekly devotional

Homeschool information & encouragement from veteran homeschoolers

FREE PRINTABLE each month

Exclusive monthly coupon code for favorite Apologia resources - ONLY offered to the Homeschool-101.com Community!

©2017 Homeschool-101.com and Apologia Educational Ministries 1

Building a Strong Bridge You may watch a video version of this activity at: https://youtu.be/wZtS_GFUPSo Background Information What are bridges? Bridges connect things that are separated. Can you think of any bridges near your home? How are bridges designed? When engineers design a bridge, they must consider:

• The function of the bridge o What will the bridge be used for – people walking, cars driving, trains

transporting, etc. • The finances for the bridge

o How much money can be spent on materials and workers • The terrain surrounding the bridge

o What do both sides of the bridge look like? How will they anchor the bridge into the ground? Is the bridge over water or land?

• The regular weather conditions o An area that has high winds will require a design different than one that is

in a calm area. What are two main things that influence bridge design?

1. Materials: Stiffer materials are harder to bend. Flexible materials can adapt easier to changing conditions (such as weather).

2. Shape: Bridges come in many designs. Some are straight across; others have arches or trusses for support. Some have cables that support the bridge structure.

Beam Bridge Arch Bridge Truss Bridge Suspension Bridge

Image credits: https://commons.wikimedia.org/wiki/File:BeamBridge-diagram.svg https://commons.wikimedia.org/wiki/File:ArchBridge-diagram.svg https://commons.wikimedia.org/wiki/File:TrussBridge-diagram.svg https://commons.wikimedia.org/wiki/File:SuspensionBridge-diagram.svg

©2017 Homeschool-101.com and Apologia Educational Ministries 2

Building A Strong Bridge Science Activity and Lesson Today you are going to be an engineer. You will design and test several bridge types. You will need: Printer paper Construction paper 2 cups the same size Ruler Pen Scissors 25 pennies 25 nickels You will do:

1. Measure and cut an 8 inch x 4 ½ inch piece out of the construction paper. Set aside.

2. Measure and cut an 8 x 4 ½ piece out of the printer paper. Set aside. 3. Place the cups upside down on the table and lay the printer paper across them.

This is your bridge. a. Do you know what type of bridge this is? It is a beam bridge.

4. Test the strength of your bridge. How many pennies can your bridge hold? a. Place a penny in the center of the paper between the cups. Keep adding

pennies one at a time, pausing in between each one to see how your bridge is holding up.

b. Continue until your bridge collapses. c. Record that number.

5. Next, fold the printer paper lengthwise into an accordion shape and place it between the cups to form a new bridge.

a. Do you know what type of bridge this is? It is a truss bridge. 6. One at a time, place pennies between the folds.

a. How many pennies does your bridge hold? Record that number. b. If your bridge can hold all the pennies, start adding nickels until it

collapses. Record that number. 7. Try a different material for your bridge. Place the construction paper bridge

between the 2 cups. Do you notice anything different between this paper an the one you just tested? Test and record how many coins the construction paper can hold.

8. Fold the construction paper into an accordion shape, and place it between the cups to form a truss bridge. Test and record how many coins it can hold.

©2017 Homeschool-101.com and Apologia Educational Ministries 3

Discussion Points:

1. In this activity, you tested two types of materials (printer (thin) paper and construction (thick) paper). Which material was stronger and held more coins?

a. You should have seen the thicker construction paper hold more coins. This is because it is not as flexible as the thinner printer paper. It did not bend as easily as the thin paper.

2. You also tested two different designs (beam and truss). Which design held more coins?

a. You should have discovered that the folded truss design was stronger. Why was that? It has to do with the strength of triangles versus a rectangle’s strength. When you folded your paper, you created many triangles. Look at the edge of your paper to see these triangles.

The triangle shape of the folded paper

b. The weight pushing down on your rectangular bridge caused it to bend and eventually collapse. The weight pushing down on your triangle had the same effect, but it was stronger because triangles support two types of forces and rectangles only support one.

i. Compression is weight pushing down. ii. Tension is a force across your bridge.

Bent downward Flattened and Spread

(compression) (compression & tension)

Try This:

To experience the strength of the triangle, place both hands against a wall and step back so that you and the wall create a triangle. You will feel the forces in your hands and feet.

©2017 Homeschool-101.com and Apologia Educational Ministries 4

wall

floor

Take It Further Directions:

• Look at the other bridge types shown, and if available, use the internet to research bridge types.

o Use your imagination and additional materials (get your parent’s permission) to create different bridges to test.

• Make sure you test both materials and structure. o What would happen if your put two or more pieces of printer paper

together? Would just adding thickness hold more coins? o What would happen if you anchored your bridge to the cups?

• Use straws, toothpicks, or popsicle sticks to create more intricate designs. How much weight can they hold? Make sure you incorporate the triangle structure into your designs!

compression

tension

VOTED #1 HOMESCHOOL SCIENCE CURRICULUM FOR GRADES K-6

Purchase at Apologia.com or via phone at 888-524-4724

NOWAVAILABLEin MP3 Audio CD Format!*

Apologia’s award-winning Young Explorers Series ignites a passion for learning and a love for God’s creation. Each of our books is written in a conversational style children find fun and engaging.

Now, five of the books in the series are available on an MP3 audio CD! The audio version is the textbook read by the author.

Reinforce reading skills and listen anywhere. The audio versions make teaching science even more fun and easier on you. They are designed to make your homeschool experience even better!

“My children struggle with reading but love the hands-on nature of Apologia science. I encouraged their love of science by adding the audio CD along with the textbook, allowing them to move at their own speed independently, and it worked wonderfully!

- Heather Laurie, Owner, SpecialNeedsHomeschooling.com

“We have used Apologia Science for several years.This year I purchased the audio CD, so we can all listen while I get other work done. I am pregnant with our sixth child, and the audio version saves me so much time!”

- Homeschooling mom

*Audio version not yet available for Astronomy or Botany. Audio version is the textbook read aloud. Audio versions do not include the notebooking journals. Audio CDs are MP3 format.