TITLE: One Two three Isaac Newton and Me AUTHOR: Jan Mader, Great Falls, MT GRADE LEVEL/SUBJECT: (9-12) The material is easily incorporated into: physical science (grade 9) and physics (grades 11 and 12) curricula. OVERVIEW: This lesson is designed to incorporate the learning cycle format with space science materials. The time frame for the entire learning cycle is approximately 10 days. This assumes that portions of the concept development will be assigned as homework outside the class period. The learning cycle develops the concepts of Newton's Laws and applies these concepts to travel in space. There are three separate exploratory labs, one for each of the three laws. Included are examples of questions that could be used to develop the concepts of Newton's Laws. I also recommend the use of the Mechanical Universe Tapes: Inertia, Newton's Laws in concept development. Navigating in Space can be used in the application phase of the cycle. The culminating activity is based on NASA's video SPACE BASICS and incorporates Newton's Laws in the analysis of flight. RESOURCES/MATERIALS: 1. Hovercraft or skateboards ** 2. Hotwheels cars and track 3. spring scales 4. meter sticks 5. 3 1000ml beakers 6. airsupplies or vacuum cleaner 7. rope and bungy cords 8. NASA video "SPACE BASICS" 9. Mechanical Universe Tapes Navigating in Space, Inertia, and Newton's Laws ** Hovercraft are easy to construct. Cut a four foot diameter circle from 1" thick plywood. Tap a 1/4" hole in the center for a bolt. You will need two washers, one metal and one that is a plastic lid from a butter dish. Drill a 1 1/2" hole 8" from the center of the circle. In this hole silicone seal a female pvc plumbing joint. Cover the bottom of the circle with 6 mil plastic, staple and duct tape the plastic to hold in place. Cut between 15 or 20 holes the size of a half dollar in the plastic at random positions. Place the bolt, plastic washer and metal washer on the underside of the hovercraft in that order. Place the nut on the upper side of the plywood. Connect an air supply or vacuum cleaner to the hovercraft's pvc opening. If you do not have a hovercraft, you may use a skateboard for that portion of the labs. One Two Three Isaac Newton and Me Exploration One PURPOSE: What affects a body's motion? RESOURCES/MATERIALS: - Part One 1. Three raw eggs 2. Three empty toilet paper rolls 3. Three 1000 ml beakers 4. One sheet of cardboard - 2' square 5. Broom 6. Paper towels 7. Hovercraft, air source and extension cord (or skateboards) ACTIVITIES AND PROCEDURES: Part One 1. Arrange the cardboard, toilet paper rolls, and beakers as demonstrated by the teacher. 2. Predict what will happen to the toilet paper rolls when you hit the cardboard sheet with the broom handle. Write the prediction. 3. Using the broom handle, hit the edge of the cardboard as per the teacher's verbal instructions. 4. Record your observations. 5. Repeat steps 1-4, but this time balance raw eggs on the toilet paper rolls. 6. Stand or sit on the hovercraft. 7. Predict your motion when the hovercraft starts to hover. Write the prediction. 8. Turn on the hovercraft and describe what happens to you and the craft. 9. Have your lab partner give you a push or pull and then let go. Describe your motion. If you do not have hovercraft, do this on a skateboard and ignore numbers 6,7 & 8 You have just experimented with Isaac Newton's First Law of Motion. Tell me what you have learned. One Two Three Isaac Newton and Me Exploration Two PURPOSE: How can an object's rate of motion be changed? What happens when a force acts on an object over a period of time. RESOURCES/MATERIALS: - Part Two 1. Hot Wheels cars of various masses and track 2. Ring stands 3. Stop watches 4. Meter sticks 5. Hovercraft, air supply and extension cords (or skateboards) 6. Bungy cords or large spring scales 7. Tape ACTIVITIES AND PROCEDURES: Part Two Design an experiment using various Hot Wheels cars, track, meter sticks and stop watches, etc. to investigate factors that affect the rate at which the motion of your Hot Wheels car changes. Write out your experimental design. Describe what you tested and the results of your tests. 1. Sit on a hovercraft. (You may use a chair) or sit on a skateboard. 2. Have your partner apply a constant force to you by pulling on a bungy cord or spring scale. 3. Describe the physical sensations that you feel. 4. Describe the motion of your partner 5. Turn about is fair play. Allow your partner to sit and you apply the force. 6. Was there a difference? Why or why not? Two down and one to go. If you were to describe Newton's Second Law of Motion to a sixth grader, what would you say? One Two Three Isaac Newton and Me Exploration Three - Can You Budge Me? PURPOSE: What force does an object exert when a force is applied to it? RESOURCES/MATERIALS: Part Three 1. Spring scales 2. Rope (at least 5 meters) 3. Hovercraft, air supply and extension cords (or skateboards) 4. Meter sticks/rulers ACTIVITIES AND PROCEDURES: Part Three 1. Take a spring scale and devise a method that allows you to apply a given force to your scale EVEN IF you can not see the numbers. 2. Hook your spring scale to your partner's spring scale. 3. Cover the surfaces of the scales with a paper folded like a tent 4. Each of you apply a force and predict what your scales will read. 5. Record forces applied, predictions and actual readings. 6. Try several combinations of forces. Record the results in a data table. 7. Place a third scale between the other two. Repeat your procedure from above. Record your results. What conclusion can you state about the forces applied from both ends? 8. Take two Hovercraft or skateboards and the rope. 9. Use two people, one on each craft, and the rope to experiment with the relative motion of each when the rope is pulled. Describe the experimental procedure that was used and the results obtained. AGAIN A DATA TABLE IS ADVISED! Three down and you're ready to apply Newton's Laws of Motion to flight. Have the students give their statements regarding Newton's First Law of Motion. Then show portions of the Mechanical Universe tape Inertia. Hopefully they will state something that resembles " Things in motion tend to remain in motion and things at rest tend to remain at rest. If they have any parlor tricks that demonstrate the first law of motion have them do them or at least describe them. 1. How were you able to change your state of motion, whether you were at rest or already in motion? A force had to act on an object to change the motion. 2. Have you ever heard of the term INERTIA? LARGE OBJECTS HAVE A LARGE INERTIA AND SMALL OBJECTS HAVE SMALL INERTIA. What do you think that inertia means? The tendency for an object to stay at rest or once moving to keep moving to keep moving is called INERTIA. HAVE STUDENTS GIVE EXAMPLES FROM EVERYDAY EXPERIENCES OF INERTIA. 3. Did the eggs have inertia? YES 4. What force acted on the cardboard to set it in motion? THE BROOM 5. What force acted on the eggs after the cardboard was removed? GRAVITY 6. What happened to you as you sat on the hovercraft and then started the air source? How were you able to change you motion? Students begin motion as soon as the frictional force is diminished by the air. Any slight motion will produce an unbalanced force that will start them moving. 7. What would you say to a 6th grader to explain Newton's 2nd Law of motion? Acceleration of an object increases as the force causing the acceleration increases. OR For a given force the smaller the object the faster its speed changes. Students very often do not understand the term acceleration. They will memorize the definition, but have no physical understanding for the term. Show portions of the Mechanical Universe tapes Newton's Laws. Placing them on a hovercraft or skateboard and accelerating them sheds a whole new light on the term. Having them watch the motion of their lab partner as that partner pulls on them with a constant force reinforces the notion that acceleration is the continual increasing of velocity. 8. What did you vary when experimenting with the hotwheels setups? Hopefully mass and angle of the track, which alters the force. 9. What did you find? That the steeper the track the faster the car went down the incline and that if the track height was maintained the smaller cars went faster. 10. Have students make a rough sketch of a force versus acceleration graph would look like and a sketch of what a force versus mass graph would look like. If they can sketch a direct relationship for F vs a and an inverse or decreasing curve for F vs mass then they some understanding of F=ma. 11. When you were sitting on the hovercraft what was the difference between being pulled with a constant force as in part 2 and being pulled or pushed and then let go as in part 1? Your body perceives accelerating forces but not uniform motion. 12. If you applied two newtons to your scale and your lab partner applied two newtons to his or her scale what reading would you get? What about a combination of three and four? Students have a great deal of difficulty with predicting the correct reading on two attached scales. It is harder with three. Be certain that the have the experiences to develop the notion of equal and opposite forces with the scales. 13. Where did you meet your lab partner when you alone pulled on the rope? Approximately the middle of the distance between them. 14. Where did you meet your lab partner if he or she pulled on the rope? Approximately the middle. Same place as before. 15. If both of you pulled on the rope, where would you meet? The same place as before the only difference is the speed at which they met. 16. Newton's 3rd Law is called the ACTION REACTION LAW. What does that mean to you. How would this law be significant in space travel? Action Reaction governs the propulsion of the shuttle into low Earth orbit. Skylab experiments and shuttle footage show action reaction very well, especially the OMS burn footage. One Two Three Isaac Newton and Me SPACE: Newton's Final Frontier Application PURPOSE: How do Newton's Laws apply to flight and space travel? RESOURCES/MATERIALS: 1. Pencil and paper 2. The NASA video Space Basics ACTIVITIES AND PROCEDURES: 1. Apply the principles of Newton's Laws to the description of a. A plane taking off and climbing to 2000 feet while accelerating to 120 mph. b. A three stage rocket launched into orbit around the Earth and then sent on to the moon. c. The flight of a shuttle from lift off to touch down. WHICH OF NEWTON'S LAWS ARE BEING APPLIED IN EACH CASE AND AT WHAT POINT ARE THEY BEING APPLIED? 2. Write your descriptions and then watch the video Space Basics. How close were your descriptions to the actual results?