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Very cold!
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Shrinking Balloons
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Cryogenic Temperatures (pdf)

Liquid nitrogen is a cryogenic liquid (of or related to low temperatures) and is stored at 77 Kelvin (-199ºC).  The liquid boils at -196ºC.  Since liquid nitrogen is so cold it has many uses as a refrigerant (including keeping some electronic equipment cool and preserving simple living organisms for long periods of time) and is also used to form inner atmospheres for the preservation of other materials.  Because of its cryogenic properties, the interaction of liquid nitrogen with other materials can lead to reactions which are scientifically interesting, as well as “wowing” for young people.  This visit requires from 45-60 minutes and may be coupled with making ice cream, using liquid nitrogen to freeze it.  The program has been matched to the Indiana Science Standards for grades 4, 5, 8, Integrated Chemistry-Physics, Chemistry, Physics.

Exploring density
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Density (pdf)

Density is the amount of mass in a given volume.  A very dense object has a lot of mass in a given volume.  One that isn’t very dense has only a little bit of mass in the same volume.  For example, the density of water is 1.00 g/mL.  This means that every milliliter has a mass of 1.00 g.  The density of gold, on the other hand, is 19.3 g/mL.  This means that every milliliter of gold has a mass of 19.3 g.  Gold is much more dense than water, so gold sinks in water.  The density of cork is 0.24 g/mL.  This means that every milliliter of cork has a mass of 0.24 g.  Cork is much less dense than water, so cork floats on water.  This visit requires 45-60 minutes.  The program has been matched to the Indiana Science Standards for grades 3-8.

Maple Grove 01
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Maple Grove 02
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The Nature of Science and Technology: Observation (pdf)

Everyday when we look at something, we see through lenses that are a part of our eyes.  To see clearly, we may need to wear eyeglasses, which have lenses.  The magnifying glass is a familiar device employing a lens.

A lens is a transparent object, usually made of glass or plastic, with one or two curved surfaces.  A lens bends the light going through it.  It changes the direction that light moves in; this is called refraction.

A magnifying lens is a lens which makes small objects appear larger.  Both sides of the lens are usually curved to form a double convex lens.

In this hands-on activity, students will learn about hands-on, investigative observation to look closely at their world, thinking by analogy, changing scale, and theorizing.  It uses a simple hands-on tool, a jeweler’s loupe (magnification tool), everyday objects from the natural and manmade world, and simple questions to develop higher order thinking skills, creativity, and scientific literacy with ease.

Thinking by analogy by asking, “What does it look like?” or “What does it remind you of?” is the tool of the scientist, poet, visual artist, inventor, humorist, and more.  Analogies become the foundation for theorizing because it naturally lends to another question, “Why is it like that?”  Intense personal observation, personal analogy, and personal theorizing leads to research and further science!

This visit requires 45-60 minutes.  The program has been matched to the Indiana Science Standards for grades 1-8.

Sound Activities (pdf)

Sounds are all around us—cars honking, phones ringing, friends talking, and dogs barking are all sounds you are probably familiar with.  So, what is sound?

Sound is a type of energy made by vibrations.  When any object vibrates, it causes movement in the air molecules.  These particles bump into the air molecules close to them, which make them vibrate too, causing them to bump other air molecules.  This movement is called sound waves.

Anything that switches back and forth, to and fro or side to side, in and out, loud and soft, or up and down is a vibration.   A vibration, then, is a “wiggle in time.”    A wiggle in both space and time is a wave.  A wave extends from one place to another.  Sound is the propagation of vibrations through a material medium.  The source of all waves is something that is vibrating.  Waves include sound, light, or whatever.

The best way to understand waves and sound is to experience them.  This visit provides an interactive experience with the presenter for 45-60 minutes.  The program has been matched to the Indiana Science Standards for grades K-8.

Mysteries of Air
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We live in a “sea” of air.  Air in many ways can seem very mysterious.  We can’t “see” it, but we can see the results from its interactions.  These interactions may be grouped into categories, including:  force due to air (including air resistance), air pressure, and moving air.  Each of these concepts will be thoroughly explored through interactive discussion and hands-on activities.

Teachers will be left with a Post-Visit packet that includes the principles and concepts taught, ideas for follow-up activities, and directions to repeat this “visit” on their own the following year.  The program has been matched to the Indiana Science Standards for grades 2-8.

What is the smallest thing you can name?  If you say “atom,” your thinking has been influenced by the ancient Greeks who came up with this idea.  Their word meant “uncut” or “indivisible.”  The Greeks thought that the atom was the smallest “building block” that combines to make up all things in the universe.  However, as years went by, scientists learned that even the tiny atom is made up of even smaller parts.  Following this came the understanding that running around the outside of the atom are the electrons and the flow of these negative charges is the source of electricity. We do not “make” or “create” electricity.

Electrons are already on the atoms.  All we do is free the electrons from the atom.   It takes a powerful force to take a proton from the nucleus of an atom, but it is quite easy to take away one or more electrons from an atom, these becoming what we call “free electrons”.  Free electrons may attach themselves to other atoms of the same body, or go to some other body.  Shoving or moving electrons into motion “makes” or “creates” electricity.

Each atom in a piece of iron is a magnet.  As such, it has a north and a south pole. However, most pieces of iron are not magnetic; their north and south poles are not lined up, but rather are randomly arranged.  When you bring a magnet near a piece of iron, the iron-atom magnets line up with the applied magnetic field, and the north poles of the iron atoms all point in the same direction.  Because the iron atoms line up, the piece of iron becomes a magnet and is attracted to the original magnet.

The “cousin” of electricity is magnetism.  A current-carrying coil of wire is an electromagnet.  Electromagnets are temporary magnets.  The magnetic field surrounding a strong magnet can temporarily magnetize objects made of iron, nickel or cobalt.  When this happens, it is said that the object has been magnetized by induction and that the object is a temporary magnet.  When the north pole of the permanent magnet touches the nail head, the nail head becomes a temporary south pole and the point of the nail becomes a temporary north pole.

When magnetized, the particles (dipoles) of the nail become lined up in one direction and the whole nail becomes a temporary magnet.  However, as soon as the permanent magnet is removed, the particles in the nail return back to their random arrangement (no longer aligned in one direction) and the nail’s magnetism is lost.

Teachers will be left with a Post-Visit packet that includes the principles and concepts taught, ideas for follow-up activities, and directions to repeat this “visit” on their own the following year.  The program has been matched to the Indiana Science Standards for grades 2-8.

Students will explore what affects the speed of water flow through soil.  Each group will make their own soil sample.  They will have the goal of either having their soil sample allow water through at a high rate, or having the water flow through slowly.  They will also present their expectations of their soil to the class.  They will be introduced to fluid flow and how it is relevant.   In the optional extension, fluid flow will be even more heavily linked to the real world.  This will be done by investigating how oil flows through mock soil samples.  The students will investigate different ways to get more oil out of their soil sample.  The program has been matched to Indiana Science Standards for grade 8 and Indiana Earth and Space Science Standards.

This project allows young scientists and engineers to explore the physical science concept of forces through the construction of polygons to discover the strongest shape.  Once students understand the need to include triangles in their constructions and understand methods they may use to accomplish this, they receive a letter from Papa Bear soliciting them as young engineers to construct a new chair for his Baby Bear due to a previous visit of a Miss Goldilocks to their home.  Students are challenged to build the strongest chair that fits Baby Bear (a Beanie Baby) for the least cost (each Lego component has be equated with a cost).  Students then share their constructions and compete to see whose chairs best fit the criteria.  Finally, students write Papa Bear a letter to convince him why he should buy their chair.  This project has been matched to Indiana Science Standards for grades 1-6.

The best way to understand light and color is to experience them.  This light and color unit begins with an initial visit providing an interactive experience with the Purdue presenter for 45-60 minutes.  The classroom teacher then facilitates the activities for the next 1-2 weeks.  The classroom teacher may become a side-by-side learner with his/her students.  The Purdue presenter then returns for a Young Scientist Conference after students and their teacher have had time for experiencing the activities and making sense of what they have learned.  During the Young Scientist Conference, students exchange and share what they have learned.  This project requires a 45-60 minute visit at the beginning and end of the unit and 1-2 weeks for the hands-on experiences.  The project is matched to Indiana Science Standards for grades 6-7.

Cosmology is the study of the universe as a whole, of the contents, structure, and evolution of the universe from the beginning of time to the future.  Different aspects of the universe are to be covered in K-12 classrooms as part of the Indiana Science Standards.  It is troublesome to see that “the universe” of a large part of the student population reduces to the Earth, the moon and a few planets.  Various aspects of cosmology have been developed into units of instruction.  For instance, The Sun’s Shadow has been matched to Indiana Science Standards for grades 3-4 and allows students to become the researcher, doing inquiry to discover how the graph they get from taking measurements of sun shadows several times a day leads to questions regarding the structure and function of the universe.

If you have any questions regarding the Purdue Physics Outreach Program, please write to us.