Physical Properties of Matter & What is in Mr. Skoldberg s Car?

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1 Physical Properties of Matter & What is in Mr. Skoldberg s Car? Name: Date: Background: Matter is anything that has mass and takes up space. Physical properties can be measured or observed using your senses without changing the matter s identity. Physical properties are characteristic of an object that can de observed or measured. For example, color, size, shape, odor, weight, length, mass, volume, density, magnetism, conductivity, flexibility, state, solubility (ability to dissolve), melting pint, and boiling point are all physical properties. Physical properties do not include what an object is used for (ex: a spoon is used for eating soup), but may help someone identify how to use a substance. For example, a physical property of copper is its ability to conduct electricity, so it is used to make electrical wire. Matter is made of atoms. An atom is the smallest part of matter that has the properties of matter and can be identified as matter. Atoms are very, very, small. As incredible as it may seem a stack of mare that a million atoms would be about as high as the thickness of a piece of paper. Over a million of them can fit on a period at the end of a sentence. Scientists have made many discoveries about atoms without ever seeing an atom. Because atoms could not until recently be seen using very powerful microscopes, researchers have relied on observations of how mater behaves. Such observations are called indirect evince- information you get about an object without actually seeing or toughing the object. AS you gather indirect evidence, you can draw a mental picture of a model of the object. Your model can be used to further study and explain facts about the object. In this investigation, you will get a gut feeling about a secret object hidden under a table as you gather indirect evidence about it. You will not be able to see or touch the secret object, however you will be able to make a mental picture of it. The main point of this experiment is not to determine exactly what the secret object is, but rather to determine the physical properties of the object-the size and shape of the object. And, can you determine ist location on the underside of the table? Problem: How can indirect evidence be used to determine the physical properties of an object? Materials: A secret object glued under a small table provided by our teacher, a book with a cardboard tube taped to it, and a marble. Procedures: 1. With your partner go to one of the Centers marked Do not look the object hidden under you table. Hold the next page of you lab in a position so that the pattern of letters written on the birds-eye-view drawing of the table top in diagram #1 matches your view of the actual table top. This view is your perspective of the table. 3. One person at your table will let the marble roll down the tube and under the table. Observe the marbles path as it rolls out from under the table. If the marble hits a leg of the table, pretend the leg isn t there and mentally extend 1

2 the path as though the leg doesn t exist. If the marble gets stuck under the table, gently slide the table aside to retrieve the marble. Return the table to is original position. 4. In Diagram #1 draw the marble s path on a birds-eye-view diagram of the table. Draw a solid line representing the marbles path as it approaches the table and exits from under the table. Draw a dashed line representing its path while under the table. Remember to draw the line from your perspective on the diagram. 5. Take turns repeating procedures 3 and 4 for several trials by passing the book and tube to the person on your right. Draw the marbles path after each trail. 6. You will begin to get a gut feeling about the secret object and will soon be able to mentally picture the size, shape, and location as though you could see it through the table. You do you not have to have the same model as the other students as your table. 7. After your teacher tell you its ok to look at your secret object, draw it actual size, shape, and location in Diagram #3. Remember, your perspective has now changed since the table has been flipped upside down. 8. Go to a different center marked 1-6 and repeat procedure on tables 4, 5, and 6. Diagram #1: Draw the marbles path on the birds-eye-view diagram of the table. Draw a solid line representing the marbles path as it approaches the table and exits from under the table. Draw a dashed line representing its path while under the table. Remember to draw the lines from your perspective. 2

3 Diagram #2: Soon you ll be able to mentally picture the size, shape, and location of your secret object. Draw you mental picture of the secret object s size, shape, and locations as though you could see it through the table. Diagram #3: After your teacher tells you it s ok to look at your secret object, draw its actual size, shape, and location. Your perspective has now changed, since the table has been flipped upside down. 3

4 Diagram #4: Draw the marbles path on the birds-eye-view diagram of the table. Draw a solid line representing the marbles path as it approaches the table and exits from under the table. Draw a dashed line representing its path while under the table. Remember to draw the lines from your perspective. 4

5 Diagram #5: Soon you ll be able to mentally picture the size, shape, and location of your secret object. Draw you mental picture of the secret object s size, shape, and locations as though you could see it through the table. Diagram #6: After your teacher tells you it s ok to look at your secret object, draw its actual size, shape, and location. Your perspective has now changed, since the table has been flipped upside down. 5

6 Conclusion Indirect evidence is information you get about an object without actually seeing or touching the object. How did your experiment help you identify the physical properties of the secret object? Application: Sometimes scientists cannot see everything that they are studying. They might be observing something that is to large, too small, or too dangerous to study directly. In these cases, scientists use models. A model represents an idea, event or object. It helps people better understand the physical properties of the object. Drawings, objects, mathematical equations, and computer simulations can all be models. In what situations are models used to study something too large, too small, or too dangerous to be studied directly. (for example, we use drawing of water molecules to better understand their structure.) Too Large: Too Small: Too Dangerous: Challenge: What phenomena do scientist study in the present using indirect evidence? How do they gather indirect evidence? Part II What is in Mr. Skoldberg s Car? Problem: Can you identify the mystery object by its physical properties? Procedure: 1. With your partner go to one of the centers marked

7 2. Do not open the bag. Make as many observations about the mystery object as you can within 5 minutes. Discuss your findings with your group members. Then list the objects properties that you can identify and the properties you cannot identify in table Analyze your data and draw a conclusion about the objects identity. 4. Share your observations, list of properties, and conclusions with your group. 5. With your group go to a different center numbered Repeat procedures Once all groups are finished the teacher will lead a class discussion about each mystery bag. 8. Answer application question. Why were you right, why were you wrong? Analyze and Conclusion: Identify the object then share your observations, list of properties, and conclusion with your group. Do not open bag yet! We Think the mystery object is Because Application: When your teacher tells you to, open the bag to see if the object was correctly identified. Discuss the reasons whey the object was either correctly or incorrectly identified with your group. Record the main ideas of your discussion below. Challenge: Play a game of 10 Questions. Partner # 1 thinks of an object, and Partner # 2 asks yes/no questions about it. #1 records the questions below. Switch roles when the 10 questions are up. Later, work independently and write a check mark next to the question asked about physical properties

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