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Welcome to Grade 3 Science

Topic C: Testing Materials and

Designs

Lesson one

Lesson 1: Introduction to Unit

Unit introduction

During this unit we will be testing a variety of materials and shapes of materials to determine their strengths and weaknesses, and which materials and shapes are better suited for certain jobs that they are used for.

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what is an engineer?

We will be engineers in science class until Christmas time. What is an engineer?

An engineer is the person who decides what materials and designs that need to be used when building a structure in order to make it safe, strong, stable, and inexpensive.

Engineers in class

As engineers in science class, we will have to test materials and designs to make sure we know what the best materials and designs are when we are building structures in order to make them safe, strong, stable, and inexpensive.

Being an engineer is a full-time job. But who do we work for?

Name Company

Before we can start testing materials and designs, we need to decide a name for our company.

Suggestions:

VOTE!!

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Company rules

Company Rules:• Respect each other, self, and the environment around you.• Practice safety: Wear hard hats at all times. (If you are not wearing a hard hat, you cannot participate in the activities)• Handle materials and tools with care and safety. (How do we hold scissors when walking?)• Work cooperatively• Complete work on time• Put all materials back where they belong

Picture time

Picture Time!!! Each engineer must have their picture taken for the company bulletin board! We will line up in rows and take everyone's picture wearing their hard hat.

SAY CHEESE!!!!!

Lesson two

Lesson 2: What is a fair test?

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What is a fair test?

What is a fair test?

Today we will be doing an activity that helps us understand what a fair test is. As engineers, we will be testing a large number of materials and designs, and we must know how to test them properly.

List of materials

2 X 4 studs

low temperature glue gun

2 3/4" round - headed nails

sandpaper

wrench

3.2 kg. bolts

hammer

pliers

latex paint

galvanized nails

6-50 grit sanding belts

metric tape measure

12" black pipe

bandsaw

plywood

wire cutters

paint thinner

Directions for discussion

You will work in small groups and discuss the following questions:

• How many items did you copy?

• Did you feel this activity was fair?

• What made the activity fair or unfair?

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Questions from discussion

How many engineers copied all items?

How many engineers copied more than 12 items?

How many engineers copied between 7 and 12 items?

How many engineers copied 6 items or less?

Questions cont'd

Was the activity fair?Yes No

What made the activity fair or unfair?Fair

Unfair

So, What makes a fair test?

So , what makes a fair test?

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Fair Test ­Scientists

Scientists must always try to control all factors (called variables) that can affect their testing by keeping them the same (constant).

If a scientist makes changes to his/her test, it is only to ONE factor (variable) for each test.

Instructions ­ Sponge activity

For the rest of class, we will finish working on our title pages and coloring the posters.

Lesson 3 Arches and Squares

Lesson 3: Arches and Squares

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You've got Mail!

You've got mail!

A contractor has been given a job to install a very large and extremely heavy steel hamburger on top of the sign for a fast-food restaurant chain. When the contractor visited the restaurant, she was faced with two options. The steel hamburger can be placed either on top of the sign that sits over the square frame surrounding the drive-through window, or on top of the arch shaped sign in front of the restaurant. Due to the large size of the burger, the contractor has concerns about its weight being held up, so she has called our company for advice. Your job is to construct a test to see which shape, square or arch, will hold the most weight so that the contractor can begin her work.

Activity: Arches and Squares

Activity: Arches and SquaresQuestion: Will a square shape support more mass than an arch shape?

Hypothesis:

Materials:• Index cards - 2 each• Plasticine - one piece each• Container and 5 masses - one set each• Worksheet #1

Procedure

Procedure:1. Make shape out of cards ( Square shape or Arch shape)2. Put plasticine on either side of the shape to stop it from moving on the desk3. Place the container on top of the shape4. Place the masses, one at a time, into the container until the shape can no longer hold the mass. 5. Record your observations on the worksheet.6. Change the shape.7. Repeat steps 2 to 5.

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Which shape was stronger?

Which shape was stronger?

Explanation ­ arch is stronger

The arch is stronger than the square shape because the mass is distributed evenly.

No one point on the arch supports a greater amount of mass than another point.

When mass is placed on an arch shape, the force of the mass is exerted sideways at the base.

Many bridges and tunnels are built using arches because of their strength. The bases of the arches are solid foundations to support the bridge.

Diagrams ­ forces on arch and square

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Parts of an Arch

There are different parts in an arch. The two parts that you need to know are the KEYSTONE and the VOUSSOIRS.

When the Romans built roadways across rivers, they used arches. They would put a wooden framework under the arch and set the stones (Voussoirs) in place for the arch. When the last middle stone was set (Keystone), they would remove the wooden framework and the arch would stand on its own.

Glossary Terms

Glossary words!

Foundation: the supporting base or lowest part of a structure often extending underground.

Keystone: The center wedge or stone at the top of an arch. The keystone holds the other stones or wedges of an arch in place.

Voussoirs: The wedges or stones making up the sides of an arch structure.

Lesson 4 Paper Beams

Lesson 4: Paper Beams

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You've got Mail!

You've got mail!

Congratulations! Your last job was very successful and you have been asked to work on a new project. The city is planning to construct new foot bridges across the Old Man River. The city is very ecologically minded so they want to use as few materials as possible to construct the bridges. The plans call for two beams per bridge, provided that they would be safe and give adequate support for the deck which is attached to the beams. You have the job of testing a variety of beam designs to provide the city with the answer of which design is best suited for the foot bridges.

Paper beams activity

Activity: Paper Beams

Question: Do all beam designs support the same mass?

Hypothesis:

Materials:• paper• scissors• tape• blocks or other objects to be used as masses• blocks for stacking• Worksheet #2, #3, #4, #5 and #6

procedure

Procedure:

1. Make a hypothesis from the shapes you see for which shape will hold the greatest mass.2. Design a fair test. Only ONE thing can be changed!

The way the paper is folded is changedEverything else stays the same:­ the size of the paper used­ the type of paper used­ the distance the beams will span (10cm)­ the positioning of the weights on the paper beams (place them in the center)

3. Using worksheet #3, #4, and #5 fold the paper beams.4. Make two stacks of books the same height.5. Place the paper beam across the books. Using your ruler, move the books so they are 10 cm apart.6. Place the masses on the paper beam one at a time until the beam can no longer hold the weight.7. Record your results on worksheet #2, and continue the procedure with the next beams.

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grpahing instructions

Now we need to graph the results that we found during our activity.

The first thing we need to do is make sure that our graph has a title.

"Comparing strength of 3 different beams"

On the bottom of the graph, write the names of the 3 different types of beams that we tested.

Accordion fold beam, rectangular beam, box girder

questions about results

How many engineers found that the accordion fold beam supported the most mass?

How many engineers found that the rectangular beam supported the most mass?

How many engineers found that the box girder supported the most mass?

conclusion

From this activity we have found that the shape of the material used affects the strength of the design.

Hollow steel beams are relatively light and very strong. The box girder is a strong and lightweight beam that is used when designing many buildings and bridges.

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Lesson 5: Testing Arches

Lesson 5: Testing arches

You've got Mail!

You've got mail!

Incredible job! Not only did the foot bridges save the city thousands of dollars, but they look great too! The city planning department, pleased with your work, has referred you to a company called Wonder World Playgrounds. Wonder World is in the midst of designing the ultimate playground and they need your help. The centerpiece of the playground is a climbing apparatus called Rainbow to the Sky. As safety is always a concern in playground design, the people at Wonder World need to know if the gap that the rainbow arch spans needs to be a certain width. Does a wider gap cause the rainbow arch to be stronger or weaker than a shorter gap? Your job is to answer this question.

Testing Arches activity

Activity: Testing Arches

Question: Will an arch spanning a gap of 20 cm support more mass than an arch spanning a gap of 30 cm?

Hypothesis:

Materials:• ruler• strips of Bristol board• blocks or other objects to be used as masses• books for stacking• Worksheet #3

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procedure

Procedure:

1. Make a hypothesis from the question.2. Design a fair test. Only ONE thing can be changed!

The distance that the arch will span will be changed.Everything else stays the same:­ the size of the Bristol board­ the size of the stacks of books­ the positioning of the mass on the arch (place them in the center)

3. Place two stacks of books 20 cm apart and place the arch between them.4. Place the masses carefully on top of the arch between the books until the arch is unable to support any more mass. 5. Record you observations on Worksheet #36. Repeat the procedure placing the books 30 cm apart.

20cm or 30 cm span supports more mass?

Which distance, 20 cm or 30 cm, allowed the arch to support the most amount mass?

Lesson 6: Support Pillars

Lesson 6: Support Pillars

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You've got Mail!

You've got mail!

What a success! The word is out and people are now calling you. Your most recent call is from the school board which has built a new school on the west side. The area around the school is growing quickly and as a result they need to construct portables. Although the school is built above the flood plane of the river, there is concern that the space where the portables must go may be below the flood plane. The solution that the engineer has come up with is to build the portables on stilts (pillars). The engineers are not sire which design would be able to hold the most weight - one central, large pillar or four smaller pillars (one on each corner of the building). You are asked to test the strength of both and report back to the school board.

Activity: Support Pillars

Activity: Support Pillars

Question: Will one large support pillar support more mass than four smaller pillars?

Hypothesis:

Materials:- tape-scissors-worksheet#4-cardboard (to place on pillars)-blocks or other objects as masses- paper (8 1/2 x 11)

Procedure

Procedure:

1. Record the question and hypothesis on worksheet #4.2. Record how you will design this activity as a fair test.

Change ONE factor, and leave all others the same.3. Roll on sheet of paper to make one large pillar and tape it together.4. Fold the other piece of paper into four parts. Cut along the folds. Roll each strip into a small pillar and tape together.5. Place the large pillar on your desk and put the piece of cardboard on top of it so it is balanced.6. Add mass one at a time on the cardboard until the pillar(s) is/are unable to hold any more.7. Record you results.8. Remove the large pillar and place the four smaller ones under the cardboard. (one at each corner)9. Repeat steps 6 and 7.10. Complete the worksheet.

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What are you going to tell the school board

What are you going to tell the school board?

The stronger structure would be the one where the pillars are at each corner of the building. This allows the mass to be distributed over a greater area and is more stable than a large pillar.

Lesson 7: Shapes of pillars

Lesson 7: Shapes of Pillars

You've got Mail!

You've got mail!

Thanks to your great work, the kids at the new school won't have to worry about their desks floating away! More success means more work! You've just returned to the office and the phone rings. It's the principal calling and he wants to know if you can help with a problem he's having with the construction of his new house. His house design incorporates an architectural feature called a portico which is a roof over a verandah, with columns on either side. The difficulty he is having is choosing which shape of column to use. The roofing tiles on the house are made of ceramics and are extremely heavy. You have been asked to test columns. He has narrowed it down to column shapes which are triangular, cylindrical or rectangular. You will conduct a fair test to discover which column shape can hold the most weight.

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Aug 12­11:42 AM

Activity: Shapes of Pillars

Question: Will a triangular shaped pillar support more mass than a rectangular or cylindrical shaped pillar?

Hypothesis:

Materials:-cardboard to place on pillars-tape-blocks or other objects to be used as masses-Worksheet #5

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Procedure:1. How is this a fair test?2. Make a cylindrical pillar by rolling a sheet of paper and taping it.3. Make a triangular pillar by folding a sheet of paper into three equal parts and attaching the two ends together with tape.4. Make a rectangular pillar by folding the paper into four equal parts and attaching the two ends together with tape.5. Place the cardboard on top of one pillar. Add mass until it can no longer support any more.6. Record results on worksheet #57. Repeat the procedure again with the next two pillars.8. Graph the results.

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Which shape of pillar is the most stable?

The cylindrical pillar is the strongest because it does not have any corners and the weight is distributed evenly.

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Because the weight is spread out evenly, the cylindrical pillars resist buckling.

They are used in buildings as support pillars and as piles.

Piles are cylinder shaped pillars set into the ground in order to provide a solid foundation for a building or deck.

Lesson 8: Testing the strength of Different stocks of paper

Lesson 8: Paper Strength Test

You've got Mail!

You've got mail!

The principal is very happy about his home, especially about the beautiful pillars in front of his home. You should feel proud of another job well done. A volunteer from a local charity has called and needs our service. They will be making posters for a fund raiser and have been given a donation of two types of paper (construction paper and bond paper). They have informed me that either works for printing posters but that the printer has concerns about the paper strength. I have agreed that we will donate our services to test the paper for charity.

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Aug 12­11:42 AM

Activity: Paper Strength Test

Question: Does construction paper support more or less mass that bond paper?

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STOP!!!!

Let's talk about properties of paper...

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Hypothesis:

Materials:-construction paper -bond paper-cup and string-blocks as masses-one-hole punch

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Procedure:1. How is this going to be a fair test? change:____ same:___________________2. Punch a hole in the bottom of the page, in the middle3. Hook the paper clip into the hole. Place the cup with the string on the hook.4. Carefully add the blocks. The paper can no longer hold the weight when the hook begins to rip the paper.5. Record the amount of blocks that the paper held.6. Draw your diagram to show your observation.7. Do the same with the next sheet of paper.

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Which type of paper supported the most mass?

The construction paper or the bond paper?

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Conclusion: The ____________ paper supported the most mass because ________ _______________________________________________________________________ .

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Lesson 9: Testing the stability of containers

You've got Mail!

You've got mail!

Our paper test results were a tremendous success! The Director of the Charity was so pleased that he passed your name on to the CEO of a large grocery store chain. He heard that they have developed a new product for their Prime Minister;s line of foods and might be in need of your services. We have been asked to test the bottle shapes that will hold their new product, Prime Minister's Double Chocolate Gooey Chewy Gumballs. Marketing reports indicate that this new product should be a runaway best seller. A concern for the grocery chain was developing a container that not only holds the product, but will be stable since large quantities will be on the shelves.

Aug 12­11:42 AM

Activity: Testing the Stability of Containers

Question: Will all shapes of containers be equally stable?

Hypothesis: I think _____________ because __________________________________ .

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Containers

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Size of the base affects the stability of the container.

The taller the container is the wider the base needs to be for stability.

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Lesson 13: The Brick Layer

You've got Mail!

You've got mail!

Did you have fun working for the school, testing the methods of joining a variety of items? The Science Consultants would like to thank you for your tremendous effort. Your daytimer tells you that you have an appointment with a local sculpture artist. When you arrive at his studio, you are faced with several small scale sculptures (models) that will be entered into a competition to celebrate the opening of a new children's park. The artist tells you that the material he wishes to use in creating the sculptures is a brick similar to the historical buildings that will be found around the park. Since the winning sculpture will be a permanent feature at the park and must last for many years to come, he wishes to know the best way to stack the bricks so that they will be both strong and stable.

Aug 12­11:42 AM

Question: Will kleenex boxes stacked in different arrangements be equally stable?

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Lesson 14: Strength of Triangles

You've got Mail!

You've got mail!

There was a great party at the opening of the new park today, and the winning sculpture was unveiled. The artist specifically named your company as being essential to the success of his winning sculpture.Back at your testing facility, some of the scientists are busy testing designs for a new food product. The product is similar to a pretzel, except that is made from corn and rice flour. Since its makers believe that it is one of the best tasting new food products, they do not want to use the traditional pretzel design. Your company has been asked to design a shape that is not only unique, but is also resistant to crumbling in the bag. You are presently at the stage where you are doing simulations before moving on to testing with the real food product.

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15 cm

22 cm

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Lesson 15: Popsicle Stick Trusses

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Aug 12­11:42 AM

You've got Mail!

You've got mail!

The last project sure was a yummy one...another satisfied customer!Some of the foot path bridges that you worked on earlier for the city, need to be made stronger so that the city's work crew can cross over in a truck. You have been asked to design trusses that can be used to strengthen some of the foot path bridges. To test your truss designs, you will need to create some models that will show you which truss design is the strongest and most stable.

Aug 12­11:42 AM

Question: Will all truss designs support the same mass?

Hypothesis:________________________.

Materials:popsicle sticksglue gun and gluecardboardbooks for masses2L milk jugs (cut to 12cm length)Worksheet #7

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Aug 12­11:42 AM

Glue - gunOperator

MaterialsManager

Time Keeper

MaterialPlacer

Recorder

Get all the materials needed for the activity.

*Be Careful*In charge of glue­gun. You are the only one who uses it.

Make sure the group stays on task. Give the group the time countdown when it is changed on the board.

Hold materials while being glued and attach to final design/structure.

Records/writes the needed information on their sheet. The group will hand this sheet in for marks.

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While the other group members are doing their job, you can finish up writing your hypothesis, materials, and diagrams on your own sheet.

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Lesson 16: Testing Nail Coatings

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You've got Mail!

You've got mail!

There is no doubt about it. You have become one of the world's top material and design companies! After several hard weeks of intensive testing investigation you feel that it is time for everyone in your company to take a break. How could this be possible with all the work that keeps coming your way?As you go through your mail, you can't believe your luck when you find a request from Parks Canada asking your company to test metals and metal coatings to find out which is best for construction of the bases of canoe landings that will be installed in each of Jasper's high mountain lakes. Since it is such a short season to open water in these lakes, the testing will require that everyone in your company goes to Jasper. You can't belive your good fortune, because part of the contract allows everyone in your company, and their families, to stay for a week at the Jasper Hotel following the work...and the bill will be paid by Parks Canada.

Have Fun!!

Aug 12­11:42 AM

Testing Nail CoatingsQuestion: Does the coating on a nail affect the rusting of the nail?

Uncoated Steel Nail Galvanized Nail Painted Nail

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Galvanized: coat metal with zinc; to coat a metal, usually iron or steel, with zinc to prevent corrosion

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We will place each nail in a petri dish with some water.

One dish will have the uncoated steel nail.

One dish will have the galvanized nail.

One dish will have a steel nail coated with clear nail polish.