Teacher s Guide written by Mary Cubello & Pauline Weber

Transcription

1 Teacher s Guide

2 Teacher s Guide written by Mary Cubello & Pauline Weber Special thanks to: Dean Elliott Science Consultant Saskatchewan Ministry of Education First Officer David Munro Sunwing Pilot For additional information, call or send orders to: McIntyre Media Inc First St., Orangeville, ON L9W 5B fax: info@mcintyre.ca Produced by: Mythic Productions

3 Video Synopsis: What is air and what does it do? Our two hosts, Professor Peter Plankton and Professor Tess Tube take students on a science field trip to discover the properties of air. Through entertaining onscreen experiments, students explore the various properties of air: air has mass, air takes up space, air has pressure, air expands when heated and air can be compressed, air can be an insulator, and air resists things moving through it. Air may be invisible but it is amazing! A Teacher s Guide is included. Curriculum Connection: Recommended for the elementary Science curriculum. Program Objectives: Students will be able to identify the properties of air: Air has mass Air takes up space Air has pressure Air expands when heated Air can be compressed Air has insulating qualities Air resists things moving through it. Students will recognize that air is made up of atoms Students will understand that air is composed of nitrogen, oxygen, and a tiny quantity of other gases and water vapour. McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca 3

4 Safety Notes Emphasize the safety precautions you are taking before performing any of the experiments or demonstrations found in this teacher s guide or accompanying video and insist that students only attempt this demonstration under the strict supervision of an adult. Before beginning any activity; Know what is expected Prepare a clear work environment Wait for permission to start Safety Tips for you and your students: 1. Read the instructions twice before beginning the activity. 2. Explain the directions in your own words to your partner or team. 3. Get only the materials that are listed. 4. Wear safety goggles (protect eyes, face, hands and body) 5. Follow the instructions one step at a time. 6. If you make a mistake stop and ask for help. 7. Clean your area thoroughly. 8. Tie back all loose and long hair. 9. Don t wear jewelery while conducting eperiments. 10. Keep equipment safe and clean. 4 McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca

5 Curriculum Correlations: YUKON - Earth and Space Science: Air Water & Soil Properties NORTHWEST TERRITORIES - Matter and Materials; Properties of Air & Characteristics of Flight NUNAVUT - Matter and Materials; Properties of Air & Characteristics of Flight ALBERTA - Air and Aerodynamics: Properties of Air SASKATCHEWAN - Earth & Space Science: Weather: Properties of Air MANITOBA - Grade 5: Weather: Properties of Air ONTARIO - Understanding Structures and Mechanisms: Flight QUEBEC - Cycle 2 (Grades 3 & 4) - Material World: Earth and Space: Matter PRINCE EDWARD ISLAND - Earth & Space Science: Weather: Properties of Air NOVA SCOTIA - Earth & Space Science: Weather: Properties of Air NEW BRUSWICK - Earth & Space Science: Weather: Properties of Air NEWFOUNDLAND - Earth & Space Science: Weather: Properties of Air McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca 5

6 Using the DVD Properties of Air Preview the video Properties of Air, and select follow-up activities from this guide to help students understand the scientific concepts presented in this program. After using this program, consider using McIntyre s video Flight, which presents related concepts that will help students understand how air is important to flight. Note that this video is divided into chapters, providing easy access to specific segments of the program as well as allowing you to use short clips to reinforce specific concepts. Introduction and Concept Development Discussion: Discuss the following with your students: Where can you find air in the classroom (all around you, inside your lungs, boxes and your backpack, e.g.) How would you describe air? What is air made of? How do you know air is around us? Can you feel it, can you hear it, can you see it? Vocabulary Development: Present the words on page 7 to the class, and ask students to volunteer to define any words for which they think they know the meaning. Write keywords from their definitions beside the words. Mark any words that no one can define with assurance. Preparing to view the video program: Explain that you will be viewing a video called The Properties of Air. Ask students to watch for words from the vocabulary list, especially words that they were unable to define. During Viewing: Pause the video after segments that contain explanations for the words that students were unable to define during the vocabulary development exercise. Discuss what they have learned, and replay the segment if it seems to be needed. Postviewing Discussion: Review with students what was learned about air while viewing the video. Did the program add to their understanding of some of the words they defined before seeing the program? Add additional keywords to the vocabulary list that was worked on during the introduction. Ask students to describe the most interesting thing they learned while viewing the video. Extended Learning Activities: Assign follow-up activities from this guide to expand the comprehension of the concepts presented in the video. 6 McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca

7 Vocabulary List Air - the invisible mixture of gases (78% nitrogen, 21% oxygen and 1% other gases and water vapour) that blankets the earth and is all around us. Air pressure - the amount of force air exerts on an object. Compress - to push or squeeze into a smaller space. Expand - to increase in size. Fluid - matter (liquids and gases) that flows. Gravity - the force which pulls objects towards the centre of the earth. Insulate - to prevent the transfer (gain or loss) of heat, energy or sound. Mass - a measurement of the amount of matter in an object. Matter - the substance of which a physical object is composed; the material substance that makes up the observable universe. Nitrogen - a colourless, tasteless odorless element that makes up 78% of air. Oxygen - a colourless, tasteless odorless element that makes up 22% of air, and is essential for life. Principle - a basic law about how things work. Properties - the special or unique qualities of something. Pressure - the action of a force against an object or an opposing force. Resistance - an opposing or slowing force. Streamlined - a design that allows an object ot move through air or liquid with little resistance. McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca 7

8 Key concepts of air and flight The activities in this guide are designed to explore the following key concepts: Easy concepts: Air is all around us. Wind is moving air. Air fills up spaces if allowed. Air can push or cause pressure on things. Air slows down falling objects such as paper, balls and parachutes. The shape and size of an object affects the nature of airflow around it, hence the air resistance. Planes and other flying things are held up by the force of air on their wings. More advanced concepts: Air in the atmosphere exerts a pressure in all directions. The atmosphere can exert a surprisingly strong force on objects. Sucking reduces pressure, causing a force imbalance towards the low-pressure region. The pressure of air is used in many applications (tires, hoists, etc.). Air pressure differences tend to equalise. A moving stream of air has reduced pressure. Air has weight. Air expands on heating, causing a pressure increase if it is contained. Hot air is less dense (or more spread out) than cold air, and rises. Air consists of a mixture of gases, one of which (O2, dioxide) is necessaryfor burning. Objects can be shaped to either minimise or maximise the force of air on them. A flat object such as a plane wing, a boomerang or a paper tube can be supported by forces that arise due to differences in airflow across the top and bottom surfaces. To every action there is an equal and opposite reaction: a stream of air (or water) forced from a balloon or rocket will cause a force back on the balloon or rocket to propel it. The force from air on a moving object depends on the surface area, and the shape of the object. Wind is moving air. Properties of Air: Air has weight. Air takes up space. Air presses on things. Air can be compressed. Air resists things moving through it. Air expands when heated. Air has insulating quality. 8 McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca

9 Properties of Air McIntyre Media Inc. tel: fax: emal: 9

10 Properties of Air Air is all around us. We can see it blowing leaves around. We can feel it blowing through our hair. It fills our lungs with each breath we take. It moves the blades on a wind turbine to create energy. However, we can t actually see it. Understanding air and its properties helps us understand its abilities and possibilities. So what is air? Air is colourless, odourless and tasteless. Air is made up of several different components. 78% nitrogen 21% oxygen Air has different properties. Air takes up space. Air has mass. Air has pressure. Air expands when heated. Air can be compressed. Air has an insulating quality. Air resists things moving through it. 10 McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca

11 Experiment #1 - Air takes up space. Objective: To detemine if air (an invisible gas) take up space. Materials: clear container, clear plastic cup, water, paper towel Procedure: Fill the container with water. Crunch up the paper towel and stuff it completely into the bottom of the plastic container. Turn the cup upside down and push it straight down into the container of water. (Do NOT tilt the cup.) Ask students to predict what will happen to the paper towel. Lift the cup straight up out of the container. Observe the paper towel. Observations: What happened to the paper towel? Does air take up space? Why do you think this happened? Explanation: Air, just like any other form of matter, takes up space. when an upside down glass that has air in it is pushed under water, the inside of the glass doesn t fill up with liquid. This is because the air that is already in the container when it is turned over stays inside of the container and pushes against the water that is trying to get in. The air trapped inside the cup keeps the paper towel dry. If the cup was tilted sideways, air would escape and water would get inside the cup and wet the paper towel. McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca 11

12 Experiment #2: Balloon Scale: Air has weight Objective: This demonstration shows that air has weight even though it is invisible. Materials: Two balloons of the same shape, a wooden rod, string. Procedure: Blow up both of the balloons so that they are the same size and tie them with string. Tie the string to either end of the rod. Tie another piece of string to the centre of the rod, so that the balloons balance as shown. You are going to let air out of one of the balloons. Ask yourself, What do you think will happen if you pop one of the balloons? Have an ADULT prick one of the balloons with the pin and see what happens. Let the air out of one of the balloons. The balloon scale will now be tilted. Questions: What do you think will happen if you deflate one of the balloons? What did happen? Why did this happen? Explanation: Air has mass. When both balloons are filled with air, they weigh the same, and therefore are balanced. When air is let out of one, they no longer have the same weight. The balloon filled with air is now heavier than the balloon with no air in it. 12 McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca

13 Experiment #3 - Air Pressure Newspaper Objective: Air is all around us and it exerts pressure in all directions. This experiment will show the exertion of air pressure on the newspaper. Materials: 1 Sheet of newspaper; Ruler (provided by teacher) Procedure: 1. Place the ruler on your desk with 1/3 of it overhanging the edge and give it a little tap. The ruler comes backwards and falls off the desk. 2. Spread the newspaper smoothly across a table. Make sure it is unfolded (otherwise air gets underneath and the results are not what they need to be). 3. Place the ruler partway underneath the paper, with one end of the ruler extending beyond the edge of the table a few inches. 4. Bring your hand down on the end of the ruler extended beyond the table edge. Questions: 1. Why doesn t the paper go flying into the air? Explanation: The pressure applied to the newspaper by the ruler by the experimenter s hand is less than the pressure applied by the air. In other words, the air is pushing down on the newspaper more than the ruler is pushing up on it. Therefore, the air pressure is holding the newspaper to the table. The force needed to lift the newspaper into the air is too large to produce with the ruler. McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca 13

14 Experiment #4: Air expands when heated. Objective: This demonstration provides clear visual evidence that air expands when it is heated. It can be used to explain why hot air rises and how wind is produced by heat energy from the Sun. Materials: Glass bottle / two large jars* / balloon / hot water and cold water ** * one jar should be suitable for hot water large coffee plungers with handle are ideal ** if possible, use boiling water from a kettle colouring the water is optional Procedure: 1. To avoid spills, check how much hot water you will need by submerging the bottle and mark the jar before the demonstration. 2. Show the class that the bottle is completely empty and stretch a balloon over the neck of the bottle so that it hangs limp (ie there should be no pressure in the balloon) 3. Discuss that air cannot escape from or enter the bottle 4. Pour cold water into one of the jars (add blue food colouring if desired) 5. Pour hot water into the second jar (add red food colouring if desired) 6. Ask the class to consider what will happen to the air inside the bottle when it is submerged in hot water (the air will heat up) 7. Submerge the bottle in the hot water and step away to prove you are not manipulating the bottle in any way the balloon will partially inflate so that it stands upright 8. Ask the class to consider what has happened reiterating that no air can escape or enter the bottle they should conclude that the air inside the bottle has expanded 9. Ask the class to consider what will happen when the bottle is submerged in cold water (the air inside will cool down again) 10. Submerge the bottle in the cold water the air inside the bottle contracts and the balloon deflates Explanation: When the bottle is heated, the air molecules inside start moving faster. These molecules now collide into the balloon with more energy resulting in increased pressure. The increased pressure causes the balloon to expand. A physical example would be that of a hot air balloon which also works on this principal as when the air is heated it causes a lot of pressure and results in liftoff of the balloon. 14 McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca

15 Experiment #5: Air resists things moving through it. Objective: For students to see how things move through air. Materials: 2 identical sheets of paper or newspaper (use recycled paper) Procedure: 1. Crumple one piece of printer paper or newspaper into a ball. 2. Put the crumpled ball in one hand and a non-folded sheet of paper in the other hand. 3. Hold both pieces of paper high above your head and drop both at the same time. 4. Repeat step 3 several times. 5. Observe which paper hits the ground first. Questions: Which piece of paper hit the floor first? Do you know why? Does shape make a difference? Why? Explanation: The crumpled ball of paper drops straight to the ground. The flat sheet of paper floats more slowly to the ground. The weight of the object does not affect the speed at which it falls. The shape of the object does affect the speed at which it falls. The larger the surface of an object, the greater the air will resist the movement of that object. Air resistance makes it harder for objects with large flat surfaces to move through the air. The flat sheet of paper has a larger surface than the crumpled ball. Automobiles, trains, and planes are designed to be more streamlined to reduce air resistance. Air resistance is known as DRAG. You may think about this the next time you see somebody jump from a plane and float to earth on a parachute! McIntyre Media Inc. tel: fax: emal: info@mcintyre.ca 15

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