A Collection of Learning Experiences on ROCKETRY

Transcription

1 11152 ELEMENTARY SCIENCE PROGRAM MATH, SCIENCE & TECHNOLOGY EDUCATION A Collection of Learning Experiences on ROCKETRY CATTARAUGUS ALLEGANY BOCES GRADES 5/6

2 TABLE OF CONTENTS Unit Overview...3 Format & Background Information Learning Experience 1 - Thrust...17 Learning Experience 2 - Major Parts of a Model Rocket...18 Learning Experience 3 - Building a Model Rocket...19 Learning Experience 4 - Stability...20 Learning Experience 5 - Rocket Stability...21 Learning Experience 6 - Making a Clinometer...22 Learning Experience 7 - Using a Clinometer...23 Learning Experience 8 - Altitude of Rockets...24 Learning Experience 9 - The Electronic Launch System Learning Experience 10 - Model Rocketry Safety...27 Learning Experience 11 - Getting Ready Learning Experience 12 - The Launch Area Learning Experience 13 - How High...34 Rocketry Student Assessment And Answer Key More Ideas Inquiry And Process Skills Glossary Teacher References...48 Major Science Concepts

3 Unit Overview ROCKETRY GRADES 5/6 Model rockets provide the opportunity for students to study basic concepts in trigonometry, electricity, aerodynamics, physics, and weather. In addition, students will learn the importance of safety while dealing with rockets and launch systems. Skills emphasized are creating models, generalizing, formulating hypotheses, identifying variables, inferring, interpreting data, making decisions, manipulating, measuring, observing, recording data, replicating and using numbers. Scheduling This unit may take from six to ten weeks to complete depending upon the goals of the teacher and interests of the students. Use of the section included in this manual called More Ideas may extend the time span of this kit. Materials to be obtained locally: Please make one student activity book for each student. Caution pencil glue scissors markers of assorted colors notebook paper hammer or mallet clipboards Remind students to wash their hands after handling any of the materials in the kit. Small objects should be handled with care. 1. Construction Construct model rockets from lightweight materials such as paper, wood, plastic, and rubber without any metal as structural parts. 2. Engines Use only preloaded factory made solid propellant model rocket engines in the manner recommended by the manufacturer. Do not change in any way or attempt to reload these engines. 3. Recovery Always use a recovery system that will return the model rocket safely to the ground so it can be flown again. 4. Weight Limits Model rockets will weigh no more than 16 oz. 3

4 (453 grams) at lift-off, and the engines will contain no more than 4 oz. (113 grams) of solid propellant. 5. Stability Check the stability of each model rocket before its first flight, except when launching a model of proven stability. 6. Launching System The system used to launch model rockets must be remotely controlled and electrically operated, and will contain a switch that will return to off when released. Stay at least 10 feet (3 meters) away from any rocket that is being launched. 7. Launch Safety No one will approach a model rocket on a launcher until either the safety interlock key has been removed or the assembly has been disconnected from the launcher. 8. Flying Conditions Do not launch any model rocket in high winds, near buildings, power lines, tall trees, low flying aircraft, or under any conditions which might be dangerous to people or property. Surface winds at the launch sight should be less than 15 miles per hour (24 kilometers per hour). 4

5 Share the sky with everyone 9. Launch Area Model rockets will always be launched from a cleared area, free of any easy to burn materials, and will only use nonflammable recovery wadding. 10. Jet Deflector Each launcher will have a jet deflector device to prevent the engine exhaust from hitting the ground directly. 11. Launch Rod Always place the launcher so the end of the rod is above eye level or cover the end of the rod with a safety cap or hand when approaching it to prevent accidental eye injury. Never place your head or body over the launching rod. When the launcher is not in use, always store it so the launch rod is not in an upright position. 12. Power Lines Never attempt to recover a rocket from power lines or other dangerous places. 5

6 Never recover rockets from electrical lines 13. Launch Targets Do not launch rockets so their flight path will And Angles carry them toward targets on the ground, and never use an explosive warhead or a payload that is intended to be flammable. The launching device will always be pointed within 30 0 of vertical. Never tilt a rock more than 30 degrees from vertical. 6

7 14. Pre-launch Test Use pre-launch tests when conducting research activities with unproven designs to determine their stability. Conduct launchings of unproven designs in complete isolation from persons not participating in the actual launching. About the Format Each learning experience is numbered and titled. Under each title is the objective for the learning experience. Each learning experience page has two columns. The column on the left side of the page lists materials, preparations, basic skills processes, evaluation strategy, and vocabulary. The evaluation strategy is for the teacher to use when judging the student s understanding of the learning experience. The right column begins with a Focus Question which is typed in italicized print. The purpose of the Focus Question is to guide the teacher s instruction toward the main idea of the learning experience. The Focus Question is not to be answered by the students. The learning experience includes direction for students, illustrations, and discussion questions. These discussion questions can be used as a basis for class interaction. A Student Assessment has been included in the Teacher s Manual and the Student Activity Manual. If you do not want the students to have the assessment beforehand, remove it from the Student Activity Manual before printing a class set of the student manuals. Background Information Students are aware of space programs in existence today and have some knowledge of previous adventures in space. They are aware of the first orbital flights around the earth, space walks, lunar landings, probes to distant planets, and space shuttles. For the most part, space exploration and travel have been abstract in nature, i.e., films, television, radio, books, and magazines. Rocketry provides students with hands-on experiences allowing the students to participate in building, testing, launching, and tracking rockets. This unit can afford students the opportunity to study concepts in trigonometry, electricity, aerodynamics, physics, weather, and language arts. Rocketry also enables the student to gain a clear understanding of the natural forces governing rocket flight. The Solid Propellant Model Rocket Engine Listed are the parts of the solid propellant model rocket engine. Use the information below to help you. 7

8 The clay nozzle is located at the bottom of the rocket engine. The narrow opening of the nozzle is designed to increase the velocity (speed) of the hot gases leaving the engine. The downward force overcomes gravity and provides the thrust needed for liftoff and acceleration of the rocket. The cardboard casing is the outside wall that holds the contents of the rocket engine. The thrust charge, when ignited, gives off hot gases that are forced through the clay nozzle at great speed. The upward force of this charge develops the propulsion needed for lift-off and acceleration of the rocket. The delay charge provides a visible white smoke to help the observer track the rocket. This charge lasts approximately three seconds. The ejection charge pressurizes the body tube forcing the nose cone and recovery system out of the body tube. This allows the recovery system (parachute or streamer) to deploy and bring the rocket safely to the ground. The clay retainer cap keeps the three charges in place. The Electrical Launch System The launch controller is a hand-held device containing the safety key, arming light, and ignition button. It is activated by inserting the safety key into the hole labeled KEY on the launch controller after the launcher has been set up as shown above. The safety key is a safety mechanism on the launch controller used to activate the electric launch system. It acts as a switch to insure that an accident will not occur. If the safety key is not in the hole labeled KEY, the launcher will not operate. When the arming light is on, the launcher is ready for ignition. The ignition button, located on the launch controller, will launch the rocket when it is depressed if the electric launch system is properly set up. The string attaches the key to the launch controller. The launch cable is at least 10 feet long and completes the electrical circuit which makes the launch possible. The battery clips are two large alligator type clips used to attach the launch cable to the positive and negative terminals of the battery. The 6 or 12 volt battery is the power source used in the electric launch system. The microclips are two small alligator type clips used to attach the electric launch system to the igniter wire that has been inserted into the nozzle of the engine. 8

9 The launch rod holds the model rocket on the launcher before firing and guides the rocket as it leaves the launcher after ignition. (The launch lug on the model rocket slides over the launch rod holding the rocket in place.) The blast deflector plate is a metal plate that slides over the launch rod used to prevent the ignited engine propellant from burning or scorching the launcher or the vegetation beneath it. The swivel mount assembly allows the launch rod and blast deflector plate to be turned and angled toward the wind. The three legs form a tripod to support the launcher. Major Parts of a Model Rocket The nose cone is the front end of a rocket. It is usually shaped so that the wind resistance will be reduced during the rocket s upward flight. The shock cord prevents the nose cone and recovery system from being torn free from the rocket during the ejection phase of the flight. It is made of elastic material (usually rubber) which absorbs much of the ejection force by stretching. The recovery system (parachute or streamer) slows the rocket s descent and return it to each undamaged. The body tube is the basic frame of the rocket. All other rocket parts are bulb on or attached to it. It must be sturdy enough to withstand the pressure of the ejection charge. The launch lug is a piece of straw paper two or three centimeters long that is glued to the body tube. The launch lug fits over the launch rod and is designed to guide the rocket during lift off. (Make sure the launch lug has several coats of glue to prevent it from coming loose during lift off.) The stabilizing fins are designed to keep the rocket traveling in a straight path. As pressure is exerted on the nose cone during flight, the rocket tends to be pushed off center. By placing the fins as far back on the rocket as possible, the forces exerted on the side of the fins will overcome the forces on the nose cone and the rocket will follow a stable, upward path. Force A force must be used any time an object begins moving, changes direction, speeds up, slows down, or stops moving. A force is a push or pull that changes the motion or shape of an object. An object that is not being subjected to a force will continue to move at a constant speed an in a straight line. 9

10 Changes in speed or direction of motion are caused by forces. The greater the force, the greater the change in motion. Given the same force, the more massive an object is, the less change in motion will occur. Whenever an object exerts a force on another object, an equal amount of force is exerted back on it. When an object speeds up, slows down, or changes direction, we know that an unbalanced force acted upon it. Gravity Gravity affects everything on Earth. However, gravity is not just the attraction between objects and the Earth. Gravity is a force of attraction that exists between any two masses, any two bodies, and any two particles. Every object exerts gravitational force on every other object. This force depends on how much mass the objects have and on how far apart they are. This force is hard to detect unless at least one of the objects has a lot of mass. Gravity is the major attractive force on objects by the Earth. This includes bodies of air and water and the things in them. Gravity pulls the air or water and the things in them toward the center of the Earth. Only the solid surface beneath the air or water prevents them from being drawn farther toward the center of the Earth. Gravity's attractive force can cause objects to roll down an incline or down hill. Gravity is the force that causes an object to be pulled toward the ground when suspended from a rope. When you throw a ball, the force of your muscles places the ball in motion. The force changes the ball s position. Another force also acts on the ball. Gravity causes the ball to fall toward the ground. Gravity is the Earth's attractive force acting on objects. Weight in pounds is a measurement of the force of gravity. In the metric system, the Newton is the standard measurement for force. Newton discovered that a force is required to change the speed or direction of movement of an object. He realized that the force called "gravity" must make an apple fall from a tree. Furthermore, he deduced that gravity forces exist between all objects. He also found that some objects required more force to move than others. The force needed to push an object at a given acceleration rate was proportional to the object's mass. An object in space, near another object, is influenced by the gravitational field of the other object. The moon is attracted towards the Earth by the Earth's gravitation. Mathematically, the gravitational attraction that two objects have for each other is as follows. 10

11 As can be seen from the formula, as the mass of either object increases, so does the gravitational force between them. As the distance between both objects increases, the gravitational force decreases. The force of the Earth's gravity pulls the moon toward Earth as the moon revolves about Earth. In effect, the moon is falling toward Earth. The moon's motion also causes the moon to move laterally (sideways) at the same time. "The moon's velocity is just enough to keep it falling toward Earth at the same rate that the Earth's curvature causes the Earth's surface to become farther from the moon. Due to the distance between the Earth's surface and center of mass, we experienced a gravitational acceleration of 9.8 meters per second per second, or 32 feet per second per second. This means that a free falling object starting from an initial velocity of zero will gain speed at the rate of 9.8 meters, 32.2 feet per second for each second of travel. Momentum A property possessed by moving objects that is the product of an object's mass, velocity and direction (or mass x velocity.) Momentum = mass x velocity The more mass something has when it is moving, the more difficult it will be to stop. It takes more forces to stop a heavy object than a light one, provided they are moving at the same speed and in the same direction (velocity). However, if two objects have the same mass, the one moving faster will be harder to stop. Finally, it may take less force to stop a heavy object if it is moving slower than a tiny object moving very fast. Consider a baseball as it is thrown by a pitcher, and then consider a bullet as it is fired from a gun. Although it has less mass, the bullet would be much more difficult to stop due to its extremely high velocity compared to the baseball. Inertia Inertia is the tendency of an object to remain at rest. It is also the tendency of an 11

12 object in motion to stay in motion and to continue traveling in a straight line. An object's inertia is determined by its mass. The more mass an object has, the more force it takes to get it to begin moving, or to get it to stop moving. Consider a bowel sitting on a table. Unless an outside force acts on the bowl, it will continue to stay motionless on the table. If someone wanted to move the bowl, they would have to apply an outside force that is greater than the force of gravity keeping it in place, thus overcoming its inertia. Now imagine a satellite orbiting the Earth. Inertia would indicate that the satellite would continue to move in a straight line. However, the gravitational pull of the Earth acts as an outside force causing the satellite to move in a circular path. If the Earth's gravity suddenly ceased to exist, the satellite would begin moving in a straight line again. Drag Drag is the resistance the air causes to an object as it moves through the air. The faster the object moves, the more drag it will experience. When you throw the ball, the fluid friction caused by the air slows down the velocity of the ball, and the Earth's gravity pulls it to the ground. The rocket you will be launching will experience the same phenomenon when its engine burns out. It too will experience air resistance that will slow it down, and gravity that will pull it to the Earth. An unbalanced force acting on an object changes its speed or path of motion, or both. If the force acts toward a single center, the object's path may curve into an orbit around the center. A passenger rounding a corner in a car seems to be pushed to the outside of the curve. This force that the passenger is feeling is centrifugal force. The force is not due to something pushing you in that direction, but by your body s inertia trying to keep you moving in a straight line. The car is curving around in front of you and intercepting you in your straight path. The car door pushes you towards the center of the curve and makes you change direction. A similar phenomena occurs with a ball on a string. The center-directed force that causes an object to follow a circular path is called a centripetal force. When you swing a ball from the end of a piece of string in a circular motion, you must pull on the string to keep it in motion, exerting a centripetal force. When you let go of the string, the ball travels in a straight path. Part of Newton s first law of motion states that an object in motion will move in a straight line unless acted on by an unbalanced force. In the case of the ball on a string, your inward pull on the string is the unbalanced force that keeps the ball traveling in a circle instead of a straight line. Upon release, the ball travels away in a straight line in the exact direction it was traveling at the very moment it was released. Centripetal Force Centrifugal Force 12

13 Newton's Second Law of Motion Any force acting on an object produces acceleration in the direction of the force, directly proportional to the force, and inversely proportional to the mass. This is the foundation for the equation for force as it relates to acceleration. The force needed to move an object, or stop one, is equal to its mass times acceleration. The relationship between an object's mass (m), its acceleration (a), and an applied force (F) is F = ma. We can rewrite this law in the following way a = F/m. This tells us that the acceleration of a body (a) depends upon the unbalanced force (F) and the mass (m) of the object. What does all this mean? It means that the rate at which an object accelerates depends upon how much force is used and how much mass (inertia) the object has. For a given amount of force, more massive objects will have a smaller acceleration than less massive objects (a push needed to move a car would send a baseball flying!) According to Newton, an object with a certain velocity maintains that velocity unless a force acts on it. The amount of acceleration is directly proportional to the magnitude of the unbalanced forces. The greater the force, the greater the acceleration. The magnitude of the acceleration is also inversely proportional to the amount of mass resisting the motion. The greater the mass, the lower the acceleration. If a football player charges into another player who is not expecting the charge, the player who is hit receives an unbalanced force. He probably gets knocked several feet! 13

14 Thrust Thrust is the forward force a rocket engine creates when it is launched. A rocket engine can produce a certain amount of thrust. To cause a satellite to reach the desired velocity, the rocket must accelerate the satellite from zero velocity to the desired velocity. The entire rock (satellite, engine, propellant, body, etc) is accelerated by the engine's trust. The total momentum achieved by a rocket is equal to the total momentum achieved by the rocket's exhaust gases. Momentum equals mass times velocity, and the exhaust gases of an Estes rocket have low mass, but their velocity is extremely fast. Because the total momentum is the same, a rocket having a mass greater than the exhaust gases will achieve a velocity lower than the exhaust gases. Newton's Third Law of Motion For every action there is an equal and opposite reaction. All forces come in pairs. The law is exemplified by what happens if we step off a boat onto the bank of a lake: as we move in the direction of the shore, the boat tends to move in the opposite direction (leaving us facedown in the water, if we are not careful!). When you walk across the floor, your foot exerts a force on the floor. The floor, in turn, exerts a force back. When a rocket launches from the pad, the exhaust from the rocket pushes down on the launch pad, and the launch pad pushes back. For every action, there is an equal and opposite reaction. In a rocket, the action comes as the rocket is pushed by the escaping gases either produced by the chemical reaction of the fuel and oxidizer combining in the combustion chamber, or the combustion of a solid propellant as in your Estes rocket. The sides of the combustion chamber prevent the gases from escaping sideways. The bases cannot escape forward since the combustion chamber will not let them. The only opening to the outside is the nozzle. Remember that a tremendous volume of hot gas is produced as the fuel is burned. These hot gases have mass and this mass can escape only through the rocket's nozzle at high velocity. This means that the gases have a large momentum (the mass of the gases times the velocity of the gases). 14

15 Helpful Hints If the model rocket uses balsa parts such as fins, sand the parts before cutting them out of the die-cast balsa sheet. Do the final sanding, squaring of edges etc., after the sanded fins have been removed from the die-cast sheet. Take an empty one or twopound coffee can to collect spent engines, wadding, and used igniters at the launch area. Do not litter the launch area. Some model rocket kits provide plastic nose cones. If painting plastic nose cones is desired, clean them with soapy water and rinse clean with clean water to remove any oil from the surface. The paint will adhere better to the clean plastic surface. Q-tips are the easiest tools to use for step 4 (Engine Mount Assembly). Simply mark the stick of the Q-tip 2 from one end. Grasp the cotton at the short end and dip the longer section into the white glue and insert into the body tube as directed. Small lumps of clay are handy when gluing fins. Stick the nose cone end of the body tube into the clay to hold the tube upright while waiting for fins to dry. A model rocket will reach a higher altitude if the ends of the launch lug are cut at an angle before attaching it to the model rocket. Provided below are the names and addresses of two of the largest suppliers of rockets, rocket supplies and rocket information. The names and addresses of other suppliers are available from your local hobby shop. Centuri Engineering Company, Inc. P.O. Box 350 Penrose, CO Estes Industries Penrose, CO Trouble Shooting If the rocket engine fails to fire, wait one minute, replace the igniter and check to make sure it is properly inserted into the nozzle of the engine. Hold the igniter wire against the propellant with the plastic igniter plug pressed tightly into the nozzle. Also, if one igniter wires touches the other there will be a short circuit and the electricity will not reach the part of the igniter against the propellant. Microclips that are touching the blast deflector plate will also cause a short circuit. As a result, the engine will not fire. 15

16 If the parachute fails to open, dust the parachute with talcum powder and carefully refold and pack it in the rocket. Reread manufacturer s instructions for packing the parachute in the rocket. If the parachute melts when the rocket is launched, add more wadding before packing a new parachute in the rocket. If the nose cone fails to eject, sand the countersunk portion of the nose cone carefully, make constant fitting checks to make sure over-sanding does not occur. Talcum powder applied to the upper surface of the body tube will also help to reduce friction. If the rocket flies erratically, check stability. Remember: (1) The further back the fins are placed on the rocket, the easier it is to make the rocket stable. (2) Move the balance point of the rocket forward by attaching nose cone weights to the base of the nose cone. (3) Fins made from balsa can be replaced with larger ones. If the wind velocity is likely to carry the rocket out of the launch area, use a streamer instead of a parachute. If the launch area is small, use a streamer. A launch area with a radius of 250 feet (approximately 75 meters) from the launcher is considered small. 16

17 Learning Experience 1: Thrust Objective: Students will observe and understand Newton s Second Law of Motion and identify the parts of a model rocket engine. Materials: For each student: Rocketry Student Activity Book Newton's Law of Motion Teacher Resource Balloon For the class: Model Rocket Engines Poster Teacher Resource Preparation: Read background information on pages 7 and 8 and 13 and 14. Use the diagram on this page as an answer key for Learning Experience #1 in the Rocketry Student Activity Book. Photocopy pages 8-11 in the Newton's Laws of Motion Teacher Resource for each student. Pass out pages 8-11 to the students and then give a mini assessment at the end. Use poster in the kit as a resource. Caution: Do not cut a rocket engine in half to view its construction. The charges in a rocket engine are explosive and dangerous. Basic Skills Development: Reading Listening Speaking Writing Evaluation Strategy: Students will describe how the thrust produced by a jet of gas (air) forces a balloon forward in the same manner the thrust of escaping gas forces a rocket forward. Vocabulary: thrust delay charge nozzle rocket force mass ejection charge thrust charge solid propellant model rocket engine acceleration Newton's Second Law of Motion What is thrust? Have each student blow up a balloon and release it. Discussion Questions: What causes the balloon to move? Why did the balloon stop moving? Why did the balloon move in the direction that it did? Have students read and follow instructions on pages 8-11 in the Newton's Laws of Motion Teacher Resource and pass out the mini assessment or give as homework. Have students complete the activity sheet for Learning Experience #1 in the Rocketry Student Activity Book. Describe the function of each stage of the solid propellant model rocket engine. Thrust Charge Cardboard Casing Clay nozzle Delay Charge Ejection Charge Clay Retainer Cap Newton s Second Law of Motion: Force is equal to mass times acceleration. 17

18 Learning Experience 2: Major Parts of a Model Rocket Objective: Students will identify the major parts of a model rocket. Materials: For each student: Rocketry Student Activity Book For the class: Rockets of the World Poster Preparation: Read background information on page 9. The teacher must assemble a rocket prior to this learning experience. Use the diagram on this page as an answer key for Learning Experience #2 in the Rocketry Student Activity Book. A Rockets of the World Poster has been provided for teacher and student reference. Basic Skills Development: Reading Listening Speaking What are the major parts of a model rocket? Discuss the major parts of the model rocket and their functions. Use the assembled rocket to show these parts. Have students complete the activity sheet for Learning Experience #2 in the Rocketry Student Activity Book. Nose cone Stock cord Evaluation Strategy: Students will identify all the major parts of a model rocket. Vocabulary: nose cone shock cord launch lug stabilizing fins solid propellant engine streamer Body tube Launch lug Stabilizing fins Solid propellant engine 18

19 Learning Experience 3: Building a Model Rocket Objective: Students will construct a model rocket that is stable enough to fly safely. Materials: For each student: Model rocket kit Model rocket A-8 engine Sandpaper 9 oz clear plastic tumbler Glue* Scissors* Markers of assorted colors* For the class: Beads Multi-purpose cement *provided by teacher What is the correct way to construct a model rocket? Students will construct a model rocket by following the instructions in the model rocket kit. As each step of the rocket is drying, place nose end down in the tumbler of beads to prevent damage. As each step is drying, you may move the students on to Learning Experience #4. Preparation: Read background information on pages 15 and 16. Follow the directions in the model rocket kit for assembly. Caution: Make sure the launch lug and fin fillets have dried before launching. There should be no paint or glue plugging the launch lug. Multi-purpose cement has been provided in the kit. The cement is used for gluing the nose of the rocket to the base. Keep multi-purpose cement away from students. Basic Skills Development: Reading Listening Speaking Mathematics Evaluation Strategy: Students will construct a model rocket by following the instructions in the model rocket kit. Vocabulary: drag fillet prelaunch test stability 19

20 Learning Experience 4: Stability Objective: Students will conduct a test for stability. Materials: For each student: Rocketry Student Activity Book Oaktag Dowel Pencil* Scissors* For the class: Fishing line Masking tape *provided by teacher Preparation: Read background information on pages Students should be able to demonstrate the concept center of pressure when they answer the activity sheet for Learning Experience #4, number 4 in the Rocketry Student Activity Book. How is a test for stability conducted? Have students complete the activity sheet for Learning Experience #4 in the Rocketry Student Activity Book. Teachers may prefer to do the actual swinging of the dowel for the stability testing as a demonstration. Students may do the center of gravity part of the activity and the cutting and taping of the oak tag fins. This allows the students to see and draw the diagrams in their student activity books as the teacher swings the dowel with and without the fins. Caution: Stability testing should be done in a large area away from other people. Basic Skills Development: Reading Evaluation Strategy: Students will correctly demonstrate how to conduct a stability test by placing fins on a dowel using masking tape and oaktag. Vocabulary: center of gravity center of pressure center of mass stability gravity 20

21 Learning Experience 5: Rocket Stability Objective: Students will conduct a rocket stability test and identify methods to improve stability. They will observe and understand Newton's First Law of Motion. Materials: For each student: Rocketry Student Activity Book Model rocket kit Model rocket A-8 engine String (50 cm) Newton's Law of Motion Teacher Resource For the class: Center of Gravity/Pressure Poster Teacher Resource Masking tape Preparation: Read background information on pages Make a chart similar to the one shown on the activity sheet for Learning Experience #5 in the Rocketry Student Activity Book. Mark the chart in 5 0 increments. Students can use the chart to complete the stability test. Photocopy pages 2-7 in the Newton's Laws of Motion Teacher Resource for each student. Pass out pages 2-7 to the students and then give a mini assessment at the end. Use poster in the kit as a resource. Caution: Always check rocket stability with an unused engine in flight position. Basic Skills Development: Reading Listening Speaking Evaluation Strategy: Students will describe two different methods that can be used to stabilize a model rocket. Vocabulary: stability fin center of pressure center of gravity How can a model rocket that is unstable be made stable? If a model rocket is not stable, it will constantly turn its nose away from the intended flight path. As a result, it will fly erratically and could be dangerous to observers on the ground. Have the students read and complete pages 2-6 in Newton's Law of Motion Teacher Resource. Have students read and follow instructions on pages 2-7 in the Newton's Laws of Motion Teacher Resource and pass out the mini assessment or give as homework. Have students complete the activity sheet for Learning Experience #5 in the Rocketry Student Activity Book. Newton's First Law of Motion: Objects in motion stay in motion and objects at rest stay at rest unless acted on by an outside force. 21

22 Learning Experience 6: Making a Clinometer Objective: Students will construct a usable clinometer. Materials: For each group of three students: Tri-wall base Printed protractor Paper clip Tangent table Glue* What is a clinometer? A clinometer is used to determine the approximate altitude of a rocket. Have a group of three students construct clinometers as shown below. For the class: Masking tape Thread *provided by teacher Preparation: It is essential that the thread is suspended from the cross mark at the top of the protractor. Make sure the thread is taped exactly as shown above. Basic Skills Development: Listening Speaking Evaluation Strategy: Students will construct clinometers. Vocabulary: clinometer tangent track tracking station 1. Glue or tape protractor to Tri-wall parallel to the top of the Tri-wall. 2. Use masking tape to tape the thread to the protractor. 3. Tie the loose end of the thread to the paper clip so it hangs slightly outside the angle calibrations. 4. Tape a tangent table to the back of the clinometer. 22

23 Learning Experience 7: Using a Clinometer Objective: Students will correctly use a clinometer to determine the height of tall objects. Materials: For each student: Rocketry Student Activity Book Notebook paper* Pencil* For the class: Measuring wheel *provided by teacher Basic Skills Development: Listening Speaking Mathematics How can a clinometer be used to determine the height of a flagpole? Discuss how to read the clinometer with the class. Read and discuss the activity sheet for Learning Experience #7, 1-4 in the Rocketry Student Activity Book. After the students have completed Learning Experience #7, 1-4, take the class outside and have them calculate the height of three tall things. Evaluation Strategy: Each student will calculate the height of a tall object using a clinometer, tangent table, and baseline. Vocabulary: clinometer tangent 23

24 Learning Experience 8: Altitude of Rockets Objective: Students will correctly determine the altitude of rockets using a tangent table, a clinometer, and a baseline measurement. Materials: For each student: Rocketry Student Activity Book Pencil* *provided by teacher Preparation: Read background information on pages Special emphasis should be given to following steps when calculating the altitude of a rocket. How high will a model rocket go? Read and discuss the instructions and example on the activity sheet for Learning Experience #8 in the Rocketry Student Activity Book. Have students complete the five problems for Learning Experience #8. Remember The longer the baseline, the more accurate the calculations for maximum altitudes. Since the calculated maximum altitudes are estimates, all maximum altitudes should be rounded to the nearest ten feet. Basic Skills Development: Reading Listening Speaking Mathematics Evaluation Strategy: Students will compute the maximum altitude of a rocket using a tangent table, baseline, and clinometer reading. Vocabulary: tangent clinometer track tracking station trajectory altitude 24

25 Learning Experience 9: The Electric Launch System Objective: Students will identify and describe the function of each part of an electric launch system. They will observe and understand Newton's Third Law of Motion. Materials: For each student: Rocketry Student Activity Book Newton's Law of Motion Teacher Resource Pencil* For the class: Electric launch system 4 AA batteries Model Rocket Launch Systems Teacher Resource *provided by teacher Preparation: Read background information on pages 8 and 9. Use the diagram of The Electric Launch System on the next page as an answer key for the activity sheet for Learning Experience # 9 in the Rocketry Student Activity Book. Photocopy pages in the Newton's Laws of Motion Teacher Resource for each student. Pass out pages to the students and then give a mini assessment at the end. Caution: This learning experience should be done with a spent engine in the rocket or no engine at all. Basic Skills Development: Reading Listening Speaking Writing Evaluation Strategy: Students will identify the components of the electric launch system and describe what each component does. Vocabulary: blast deflector plate swivel mount assembly launch controller launch rod microclips What is an electric launch system? Set up the electric launcher as shown on the next page. Read the Model Rocket Launch Systems Teacher Resource and discuss with students how the electric launch system works. Have students read and follow instructions on pages in the Newton's Laws of Motion Teacher Resource and pass out the mini assessment or give as homework. Students should complete the activity sheet for Learning Experience #9 in the Rocketry Student Activity Book. Newton's Third Law of Motion: For every action there is an equal and opposite reaction. 25

26 Learning Experience 9 continued Page 2 26

27 Learning Experience 10: Model Rocketry Safety Objective: Students will understand and abide by the rules of the Model Rocketry Safety Code. Materials: For each student: Rocketry Student Activity Book Preparation: Read background information on pages 3-7. Basic Skills Development: Reading Listening Speaking What rules should be followed when a model rocket is launched? Discuss each item of the Model Rocketry Safety Code in detail with the students on the activity sheet for Learning Experience #10 in the Rocketry Student Activity Book Evaluation Strategy: Students will follow the Model Rocketry Safety Code during the launching of any model rocket. Vocabulary: launch area launch acceleration 27

28 Learning Experience 11: Getting Ready to Launch Objective: Students will complete final preparations for launching. Materials: For each student: Model rocket kit Model rocket A-8 engine Igniter and igniter plug Igniters And Their Use Teacher Resource For the class: Baby powder Model Rocket Launch Systems Teachers Resource Model Rocket Flight Profile Poster Teachers Resource Masking tape Wadding Preparation: Photocopy Igniters And Their Use Teacher Resource and give a copy to each student. Read over this before finishing engine assembly. Read the Learning Guide for Model Rocket Launch Systems Teachers Resource. Use poster in the kit as a resource. How should the recovery system, engine and igniter be installed? Prior to launching students should review the Model Rocketry Safety Code. Read the Igniters and Their Use Teacher Resource prior to launching. Pre-launch preparations are as follows: 1. Stability testing should be complete. 2. Pack two or three squares of wadding into the body tube of the rocket before inserting the streamer. 3. Insert streamer into tube. (Baby powder sprinkled on the streamer helps reduce friction and allows the recovery system to deploy freely.) Tuck the strings and shock cord into the rocket body and put the nose cone in place. Basic Skills Development: Listening Speaking Mathematics Evaluation Strategy: Each student will properly install a recovery system, engine, and igniter in a model rocket. Vocabulary: igniter nichrome wire streamer wadding 28

29 Learning Experience 11 continued Page 2 Igniter Installation: About 90% of all problems with engine ignition are caused by the igniter not being properly installed and securely held in place in the engine. The igniter must touch the propellant at the moment the igniter is heated for ignition. 1. Cut tape separating igniters. Do not remove tape. 2. Separate plug from strips of plugs. 29

30 Learning Experience 11 continued Page 3 3. Insert igniter into engine. Igniter must touch propellant. Do not bend igniter. Propellant 4. Insert plug into engine nozzle. Keep wires straight 5. Push plug firmly into engine. 30

31 Learning Experience 11 continued Page 4 6. Bend igniter wires back and form leads as shown. Hold down plug with thumb when you bend wires. 7. Make sure micro-clips are clean. Attach micro-clips to the igniter wire leads as shown. Arrange the clips so they do not touch each other, the launch rod or the metal blast deflector. 31

32 Learning Experience 12: The Launch Area Objective: Students will set up a launch area that is safe for both launchers and viewers. Materials: For the class: Electric launch system Measuring wheel Ball string 4 metal stakes Hammer or mallet* *provided by teacher Basic Skills Development: Listening Speaking Evaluation Strategy: Students will set up a rocket launch area. Vocabulary: launch area trajectory tracking station track What is an easy way to set up a launch area? Select as large area to launch rockets. Football fields, parks, and large playgrounds will do nicely. The larger the launch area, the better the chance for rocket recovery. OBTAIN PERMISSION TO USE THE AREA. The minimum launch site dimensions for an A8-3 engine powered rocket is 250 feet in all directions from the launcher. 1. Construct the baseline at a 90 0 angle to the wind direction. 2. Use the measuring wheel to construct a baseline from the launcher to the tracking station. (Baselines of 100 feet are suggested for both one and two station tracking.) Drive a metal stake into the ground to designate each tracking station. 3. All students waiting to launch their rockets must stay at least twenty feet behind the launcher in the waiting area. Use the string and two stakes to set up an area for the students. (See on the next page) 32

33 Learning Experience 12 continued Page 2 Stake Waiting Area Stake tracking station #1 Twine Stake Launcher Recovery area Stake tracking station #2 33

34 Learning Experience 13: How High? Objective: Have students plan and organize a safe and successful launch experience and determine altitudes of all rockets launched. Materials: For each student: Rocket (ready to launch) For the class: Model Rocket Flight Profile Poster for Teacher Resource Measuring wheel Baby powder Tangent tables 3 rocket launch data sheets Electric launch system Sandpaper for cleaning microclips 2 clinometers 3 pencils* 3 clipboards* *provided by teacher Preparation: Trackers, recorders, recovery team, and a launch control officer should be changed after a few launches to give each student the opportunity to perform as many of these tasks as possible. Use poster in the kit as a resource. What must be done to have a successful launch? The rocket launch data sheet should be complete. Names of students should be listed in order. Assign one tracker with a clinometer and one recorder with a clipboard, Rocket Launch Data Sheet, and a pencil for each tracking station. Assign two students to the recovery team. Assign a launch control officer with a clipboard, Rocket Launch Data Sheet, and a pencil. The launch control officer s duties are to announce rocket firings, signal trackers, and commence countdown procedures. Launch rockets. Calculate maximum altitudes of rockets using baseline data, clinometers, and tangent tables. Record results. Evaluation Strategy: Student s will launch a rocket and calculate a rocket s maximum altitude. Vocabulary: tangent maximum altitude clinometer apogee 34

35 Name: Rocketry Student Assessment Date: Directions: Read the question carefully and answer based on your knowledge about rocketry. Circle the correct answer. 1. The center of gravity refers to 1. the middle of the earth. 2. a position on the rocket one inch in front of the launch lug. 3. the middle of the rocket. 4. the balance point of the rocket. 2. Pre-launch tests for stability of model rockets are done 1. with spent (used) engines in place. 2. with new engines in place. 3. without engines in place. 4. using any of the above. 3. Engines for model rockets 1. contain liquid propellant. 2. are smokeless. 3. contain solid propellant. 4. have only a thrust charge and ejection charge. 4. The function of the blast deflector plate is to 1. give the exhaust from the ignited engine something to push against. 2. prevent short circuits. 3. hold the launch rod steady. 4. prevent burning or scorching of the launcher or vegetation beneath it. 5. If a streamer melts during launching, which of the following should you do before you launch the next time? 1. Change to a parachute. 2. Remove the streamer and do not replace the recovery system. 3. Replace the streamer and use more wadding. 4. Use a smaller engine. 6. The forward force produced in reaction to gases escaping from an engine s nozzle is called. 1. thrust. 2. velocity. 3. drag. 4. gravity. 35

36 Rocketry Assessment Page 2 7. Which part of the launch equipment holds the rocket upright and guides its initial upward flight? 1. launch rod. 2. tripod legs. 3. blast deflector plate. 4. microclips. 8. Recovery systems on model rockets are: 1. never used on windy days. 2. often destroyed if too much wadding is used. 3. necessary for safe rocketry. 4. optional or unnecessary. 9. Excessive glue or paint and rough surfaces on a model rocket will cause 1. thrust. 2. velocity. 3. trajectory. 4. drag. 10. Which part of the model rocket engine accelerates the exhaust gases to a high velocity as they are expelled from the engine? 1. cardboard casing 2. clay retainer cap 3. ejection charge 4. nozzle 11. If a model rocket accidentally gets caught in power lines, 1. get a ladder to reach it. 2. call the power company and ask them to recover it. 3. throw stones at it and try to knock it down. 4. put on rubber boots and climb up to get it. 12. Which part of a model rocket is designed to cut down drag? 1. fins 2. nosecone 3. launch lug 4. engine 36

37 Rocketry Assessment Page The curved path a rocket takes from the time it leaves the launch pad to the time the recovery system is ejected is called 1. trajectory. 2. tangent. 3. clinometer. 4. stability. 14. Identify the part of model rocket whose chief function is to provide stability in flight. PART II 1. launch lug 2. engine 3. nosecone 4. fins 15. Draw and label a diagram of a model rocket engine using the following terms: ejection charge clay nozzle thrust charge clay retainer cap cardboard casing delay charge 16. Describe the function of each of the three charges in a model rocket engine. 17. Explain the location and purpose of wadding in a model rocket. 37

38 Rocketry Assessment Page Draw and label a diagram to illustrate a safely planned launch area. 19. Explain how energy is created and transferred from the launch controller to the model rocket engine. Begin with the insertion of the safety key and end with the ignition of the engine. 20. Use a tangent table and the following information to find the altitude of a model rocket. ROUND MAXIMUM ALTITUDE TO THE NEAREST 10 FEET. Show all work. Both baselines are 100 feet. h is the altitude of the rocket. h baseline = tangent of angle One station tracking: Angle = 78 degrees Two station tracking: Angle # 1 = 49 degrees Angle # 2 = 61 degrees 38

39 Rocketry Student Assessment Key Refer to Learning Experience 1 in Teacher s Manual. 16. Refer to Learning Experience 1 in Student Activity Book. 17. Wadding is located inside the body tube between the engine and the recovery system. Its purpose is to protect the recovery system from the heat of the ejection charge. 18. Refer to Learning Experience 12 in Teacher s Manual. 19. When the safety key is inserted into the launch controller a circuit is completed allowing the energy stored inside the four AA batteries to flow through the launch cables to the microclips and into the igniter wires. The high resistance nichrome wire heats up rapidly causing the coating at the tip of the igniter to burn and ignite the solid propellant of the thrust charge. 20. One station tracking: h = tangent of 78 degrees x 100 ft. h = 4.70 x 100 ft. h = 470 feet MAX. ALT. Two station tracking h = tangent of degrees x 100 ft. 2 h = tangent of 55 degrees x 100 ft. h = 1.42 x 100 ft. h = 142 ft. h = 140 ft. MAX. ALT. 39

40 MORE IDEAS Language Arts Use the following words correctly in complete sentences. Have students keep a glossary of terms as they proceed through the unit. gravity acceleration altitude center of gravity trajectory apogee shock cord thrust ring thrust charge fin nose cone drag launch lug model rocket engine shroud lines wadding nichrome wire stability launch controller ignition button solid propellant blast defector plate streamer center of pressure launch area nozzle parachute clinometer launch rod fillet prelaunch test igniter ejection charge rocket microclips delay charge arming light thrust safety key Have students describe how they assembled their rockets. Edit and review paragraphs making sure sequence is correct. Creative writing. How has space travel changed our way of life? I orbited earth and. Journal writing: Have students keep a daily journal to record a summary of each day s activities and progress in the construction of their model rocket. Art Construct a miniature Cape Canaveral as a class project. Identify all parts of the area and describe the function of each. Social Studies Investigate the history of space flight. Have each student select a topic and write and/or construct a short research project based on in depth study. Topics may range from pioneers such as Robert H. Goddard and Wernher von Braun, to the first U.S. astronaut to orbit the earth, John H. Glenn, to the various recent space projects. 40