LIVE INTERACTIVE YOUR DESKTOP October 24, 2011 Center of Mass and Center of Pressure: Engineering a Stable Rocket Presented by: Rachel Power

NASA Explorer Schools Presents

Outline for Web Seminar  Navigating the Guide  Navigating the Activity  Building a Launcher  Building a Rocket  STEM Concepts  Additional Resources

explorerschools.nasa.gov

Table of Contents  A Pictorial History of Rocketspg 1  How Rockets Workpg 19  Applying Newton’s Lawspg 24  National Standards Matrixpg 31  Suggested Grade Levelspg 33  Additional Explorations pg 140

Which civilization is credited with the first recorded use of rocket propulsion? A. Chinese B. Russian C. Greek D. German

A Pictorial History

How Rockets Work

Applying Newton ’ s Laws

National Standards Matrix

Suggested Grade Levels

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Teacher Pages

Student Pages

Calculating Area

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High-Power Launcher  Low cost  Parts in plumbing or hardware stores  Easy to assemble and use  Bicycle pump or air compresso r

Shopping and Assembly

Pop! Rocket Launcher  Minimal cost  Even easier to assemble and use  Parts at plumbing or hardware stores

Shopping and Assembly

Which type of launcher do you plan to use? A. High-power launcher B. Pop! rocket launcher C. Undecided

Safety Plan and Tips

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Making Basic High-Power Paper Rockets

EngineeringDesignProcess

Materials

Assembly

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Sounding Rockets

Forces on a Rocket weight thrust drag lift

Rocket Stability center of pressure center of gravity

x For simple shapes:  Balance rocket using a string or an edge such as your finger or meter stick For simple shapes:  Balance rocket using a string or an edge such as your finger or meter stick Finding Center of Gravity

For more complex shapes:  Hang the rocket from some point  Drop weighted string from point  Draw line on rocket along string  Repeat from another point  Find the point of intersection For more complex shapes:  Hang the rocket from some point  Drop weighted string from point  Draw line on rocket along string  Repeat from another point  Find the point of intersection x Finding Center of Gravity

x  Trace the shape of rocket on cardboard  Cut out the shape  Determine the balance point  Trace the shape of rocket on cardboard  Cut out the shape  Determine the balance point Finding Center of Pressure

c g W = w n d n + w b d b + w f d f W = w n + w b + w f W = w n + w b + w f c g W = w n d n + w b d b + w f d f W = w n + w b + w f W = w n + w b + w f Mathematical Approximation Center of Gravity

c g = w n d n + w b d b + w f d f c g = w n d n + w b d b + w f d fW W Mathematical Approximation Center of Gravity

Mathematical Approximation Center of Pressure c p A = a n d n + a b d b + a f d f A = a n + a b + a f A = a n + a b + a f c p A = a n d n + a b d b + a f d f A = a n + a b + a f A = a n + a b + a f

c p = a n d n + a b d b + a f d f c p = a n d n + a b d b + a f d fA A Mathematical Approximation Center of Pressure

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Rocket Wind Tunnel

Launch Altitude Tracker

Additional Explorations Calculating Altitude

Advanced High-Power Paper Rockets

Collaboration

Feedback

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Thank you to the sponsor of tonight's Web Seminar: This web seminar contains information about programs, products, and services offered by third parties, as well as links to third-party websites. The presence of a listing or such information does not constitute an endorsement by NSTA of a particular company or organization, or its programs, products, or services.

National Science Teachers Association Dr. Francis Q. Eberle, Executive Director Zipporah Miller, Associate Executive Director Conferences and Programs Al Byers, Assistant Executive Director e-Learning LIVE INTERACTIVE YOUR DESKTOP NSTA Web Seminars Paul Tingler, Director Jeff Layman, Technical Coordinator