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Composite Material Experiment - Contenido educativo
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NASA Connect Segment involving students in an activity that investigates the strenth and deflection of composite material with and without reinforcement. It reviews vocabulary including polymer, fiber, stress cracks, and maximum deflection.
Hi, we're students from Hugo A. Owens Middle School in Chesapeake, Virginia.
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NASA Connect asked our science and math teachers, Ms. Bernadette Smith and Ms. Angela Williams,
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to have our class investigate the strength and deflection of a composite material
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with and without the use of a reinforcement.
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Ms. Smith reviews some vocabulary terms which will help us in our composite research.
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A polymer is a large molecule built by the repetition of small, simple chemical units.
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Nylon, polyester, Teflon, and rubber are examples of polymers.
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A fiber is a long, thin strand of material such as nylon, hair, wood, or even glass.
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Stress cracks are external or internal cracks in a body caused by the application of forces to the body.
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Maximum deflection is the largest deflection that a body or structure is allowed to take while in use before failure.
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Having reviewed these terms, we are now ready to divide into our research teams.
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Here are the procedures we followed to do the experiment, and you can do it too.
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Cut out or buy six pieces of 8 by 15 centimeter poster board.
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Two of these will be used without any reinforcement or binder.
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Two will be used with the epoxy compound, and two will be used with the epoxy and a sheet of fiberglass.
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For the epoxy preparation, put on the rubber gloves and safety goggles.
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Then, squeeze out enough of the two-part epoxy to make a pool about the size of a quarter on the back of the poster board.
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Mix thoroughly with the Popsicle stick.
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Spread the epoxy evenly over the surface of the first poster board.
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Take the second poster board and press the two pieces together.
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Weigh the sample down to help consolidate it.
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After you've done this, let the epoxy-reinforced poster board dry for 10 minutes.
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Now we will prepare the fiberglass epoxy poster board composite.
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Spread the epoxy on the one side of the board with the epoxy and lay the piece of fiberglass on top of the glue.
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Once this is done, lay the back of the second poster board on top of the fiberglass and press to form a sandwich.
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The thickness of each sample is measured for strength calculation.
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Our math teacher, Mrs. Williams, provides us with the numbers.
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While the epoxy poster board and the fiberglass board are drying, it's time to begin testing the nine composite poster boards.
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Take the two flat meter sticks and have them bridge a space between the two desks.
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Using the ruler, measure the inside distance between the sticks at 6 centimeters apart so they will support the poster board.
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This is called the span.
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Once you have done this, tape down the meter sticks onto the desks.
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Tie one end of the string onto a milk jug handle and tie the other end onto a loop big enough to slide over the lengthwise part of the poster board.
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Be sure to measure out enough string so that the milk jug will dangle 5 centimeters above the ground.
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This distance from the ground is our design maximum deflection and is the design requirement of this experiment.
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Now set the poster board over the meter sticks and let the jug hang down gently.
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Carefully pour the water into the jug until the test material is dense enough to send the jug to the floor.
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Pick up the jug with the water and the string.
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Place these onto the scale to determine how much weight caused the poster board to bend or flex.
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Once we have tested the plain board, the epoxy board, and the fiberglass board, we will compare our data with the other teams.
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Now we have finished our experiment.
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Mrs. Williams helped us to think about what our data might tell us and what mathematical statements we might write to analyze the data.
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Okay, joining me in the studio are Roberta Cano, a materials research engineer at NASA Langley here in Hampton, Virginia.
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Also, Bill Millward from the Space Transportation Program at Marshall Space Flight Center in Huntsville, Alabama.
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But, before we take to our researchers and let you ask some questions,
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let's give you a chance to do your own computations using the data from the experiment you just saw.
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Then, after this segment, our two researchers will be answering your email questions and taking questions from our viewing audience.
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Okay now, look carefully at the data and using the information in the following diagram,
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work with your fellow students to answer the questions as read aloud by Dr. Catherine Fay.
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Based on the data presented, which specimen has the highest flex strength? Why?
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Based on the data presented, which specimen has the lowest flex strength? Why?
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Based on the data presented, which specimen has the highest flex strength? Why?
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Why is there such a big difference between the flex strengths of specimens 1 and 2?
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Why is there such a big difference between the flex strengths of specimens 1 and 2?
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Thanks.
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- Idioma/s:
- Materias:
- Matemáticas
- Niveles educativos:
- ▼ Mostrar / ocultar niveles
- Nivel Intermedio
- Autor/es:
- NASA LaRC Office of Education
- Subido por:
- EducaMadrid
- Licencia:
- Reconocimiento - No comercial - Sin obra derivada
- Visualizaciones:
- 379
- Fecha:
- 28 de mayo de 2007 - 16:53
- Visibilidad:
- Público
- Enlace Relacionado:
- NASAs center for distance learning
- Duración:
- 06′ 50″
- Relación de aspecto:
- 4:3 Hasta 2009 fue el estándar utilizado en la televisión PAL; muchas pantallas de ordenador y televisores usan este estándar, erróneamente llamado cuadrado, cuando en la realidad es rectangular o wide.
- Resolución:
- 480x360 píxeles
- Tamaño:
- 41.10 MBytes