Southern Nevada Regional Professional Development Program. What happens when water changes to a solid?

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1 3-5 Physical Science What happens when water changes to a solid? Two large soft vials with caps One plastic 50 ml syringe Plastic ice tray Water Freezer compartment 1. Completely fill the ice tray and two vials with water 2. Cap both vials tightly 3. Fill the plastic syringe to the 40 ml mark 4. Place the vials and syringe in the freezer for 24 hours 5. What happened to the water? What did you notice? Unlike other material, water expands as it approaches the freezing point. The surface of the ice tray may be rippled showing a pattern first of expansion, then of contraction as the water became frozen. The lids on the vials will be bulged or forced off due to the expansion of the freezing water. Because of this expansion, water-cooled engines require an anti-freeze, which lowers the freezing point of the engine coolant. Most engines also have freeze plugs which are designed to pop out, just like the top of the small bottle, to prevent serious damage to the engine. Outside water pipes are usually turned off and drained during winter months in cold climates. s P.5.A.1 Students know matter exists in different states (i.e. solid, liquid, gas) which have distinct physical properties. P.5.A.2 Students know heating or cooling can change some common materials, such as water, from one state to another. 9

2 3 5 Physical Science Bouncing Light Two cardboard tubes (paper towel tubes) A flashlight Mirror Two people 1. Hold a mirror up near the edge of a table. 2. Ask a friend to hold one tube at an angle to the mirror. 3. Shine the flashlight down it. 4. Hold your tube next to the first one. 5. Look through it and move it around until you see the light shining straight at you. Reflections are caused by light bouncing off things. An alternative experiment would be to direct a beam of sunlight along a wall by reflecting it off a mirror. NOTE: Never look directly at the sun or its reflection in a mirror because it can damage your eyes. P.5.C.1 Students know light can be described in terms of simple properties (e.g. color, brightness, reflection). 10

3 K-2 Physical Science 3-5 Earth Science 1 Balloon, round 1 Balloon pump 1. Explore with the materials. 2. What did you find out about air? 3. What is air? How can you tell if air takes up space? Air is a form of matter known as a gas. It has observable properties. It can fill up the balloon and not be smashed flat without popping the balloon or letting the air out first. Thus air takes up space. Nevada State Standards P.2.A Students understand that matter has observable properties. E.5.A.5 Students know air is a substance that surrounds us, takes up space, and moves around us as wind. 11

4 3-5 Physical Science One shallow dish Water Window in the sun Piece of paper Colored Light 1. Fill a shallow dish with water. 2. Put it by a window in the sun. 3. Slant a small mirror in it facing the sun. 4. Hold a piece of paper above it and move the mirror until the sun is shining through the water until reflected on the paper. 5. What is happening and why? 6. Record results, with illustrations. Light travels in a straight line. Mirrors reflect light. Water is a natural prism which bends the light into a spectrum. The colors you see in the rainbow are always in the same order. Additional questions. What are the colors in the rainbow? What are they? What other colors do you see in the rainbow colors? P.5.C.1 Students know light can be described in terms of simple properties (e.g. color, brightness, reflection). 15

5 3 5 Physical Science Plastic box Eight thick rubber bands High Sounds and Low Sounds 1. Stretch the rubber bands around the box. 2. Tighten them by catching them on the edge of the box, to give each one a different note. 3. The tighter the rubber band, the higher the note makes. 4. Try tuning the rubber bands so you can play to scale. Sound is produced by vibrations. Short strings will produce a high pitch. Long strings will produce a low pitch. Alternative experiments: 1. Find some bottles the same size. Pour different amounts of water into them tap them. What do you notice? 2. Use rubber bands that are of different thicknesses. See if this might change the sounds that are made. P.5.C.2 Students know the wave characteristics of sound. 16

6 3 5 Physical Science Can you light the bulb? (to make one mystery board) Manila file folder Six brads Aluminum foil (cut into strips) or 20 gauge wire pieces (stripped) Flashlight bulb Masking Tape 1. On one side of the file folder make three holes across (about 3.5 inches between each hole) 2. Label each brad from A F. 3. On the inside of the file folder connect two of the brads with either an aluminum foil strip or wire (ex. A and F). Up to two connections per file folder. 4. Tape the outside of the folder closed. 5. Using the wires and D-cell see if you can light the bulb by completing the circuit. A B C D E F A circuit is a pathway through which electric current flows. A closed circuit allows electricity to flow. Create several folders with different connections. P.5.C.5 Students know the organization of a simple electrical circuit (i.e. battery or generator, wire, a complete loop through which the electrical current can pass). 17

7 3 5 Physical Science Light and Shadows Dark room Flashlight Book, spoon, pencil, jar, marbles, ruler, paper, rock 1. In a dark room shine a light onto each object. Which objects let the light through? Which objects do not let the light through? 2. Some things let the light through. You can see clearly through theses things. 3. Some things let light through but they scatter the light. If you look through these things everything looks blurred. 4. Many things do not let any light pass through them. You cannot see through them. They are said to be opaque. P.5.C.1 Students know that light can be described in terms of simple properties (e.g. color, brightness, reflection). 18

8 3 5 Physical Science Spoon Chimes String Metal spoon Plastic cup (punch a hole in the bottom of each cup) Pencil 1. Tie the string to the spoon. 2. Thread the other end of the string through the hole in the bottom of the cup. Knot the end inside the cup. 3. Hold the cup over your ear with the spoon dangling away from your body. 4. Have a partner tap the spoon with the pencil 5. Listen to the sound Hitting the spoon causes it to vibrate. The vibrations bounce the molecules in the air, which in turn bumps into the other molecules producing a spreading pressure in the air. If this pressure wave travels into your ear and hits your eardrum, your eardrum and the tiny bones behind it vibrate just like the spoons did. Your brain then transmits this information as a sound or an echo. Extension Activities 1. Have different lengths of the same type of string. Does this make a difference in the sounds? 2. Try using different types of string, but make sure they are the same length. Yarn, dental floss, and twine are some suggestions to use. Do you notice any differences in the sounds? P.5.C.2 Students know the wave characteristics of sound. 19

9 3 5 Physical Science How can sound cause an object to move? Tuning Fork Ping Pong Ball taped to a length of string Shoe or wooden surface Plastic cup Water 1. Strike the tuning fork against a wooden surface or a shoe. 2. Hold it against a suspended ping-pong ball. 3. What is happening to the ping-pong ball? 4. Record your observations and thoughts in your science notebook. 5. Strike the tuning fork. 6. Place just the ends of the tuning fork into the water. 7. What do you notice? Record your observations and drawings in your science notebook. The ping pong ball will bounce away from the rapid vibrating motion of the tuning fork, thus providing that sound is a form of energy produced by the vibration of matter. The vibrating tuning fork will cause the water to splash out of the cup. P.5.C.2 Students know the wave characteristics of sound. 20

10 3 5 Physical Science Magnet Steel ball What s the attraction? 1. Place the magnet on the table. 2. Place the steel ball on the table about 2-3 cm. from the end of the magnet. 3. Let go of the steel ball. 4. What happened? Record your observations and drawings in your science notebook. The magnetic force causes magnetic interactions. A force is a push or pull. P.5.B.3 Students know a magnetic force causes certain kinds of objects to attract and repel each other. 21