Exploring Motion. Introduction. Att. Number

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1 Exploring Motion Introduction Newton s three laws of motion describe the interaction of forces that control movement. The first law states that a body in motion will remain in motion unless acted upon by an unbalanced force. The same is true for a body at rest. The second law predicts that when an unbalanced force is applied to a body it will produce acceleration; while the mass of the body (inertia) resists acceleration. The third law explains the result of the interaction of more than one force. Every action has an equal and opposite reaction. Simply put, momentum, defined as the product of mass and velocity, is conserved by a system of colliding bodies. There are several variables that are often accounted for while doing motion equations; they are friction and gravity. For mathematical simplicity these forces are usually assumed to be zero, but are in fact constantly impacting motion. We have learned that an unbalanced force is required to put an object in motion, as when we construct a paper airplane and toss it (apply a force) into the air. However, it is only the initial force from our arms that gives the paper plane motion. Soon it is slowed down by gravitational as well as frictional forces and comes crashing to the ground. There are four forces that act upon and compete with any airborne object. Thrust and lift produce the force needed for flight, while gravity and drag have the reverse effect. A properly constructed wing will produce an airfoil when in motion that will cause air to move slowly over the curved wing top and quickly across the flattened wing bottom. Thrust from the engine moves the plane forward which creates the airfoil that generates the lift force by creating air pressure gradients that circulate around the wing. Thrust must exceed drag and lift must exceed gravity for the flight to continue.

2 Independent Variable: Mass Dependent Variable: velocity and acceleration Purpose: To construct a paper airplane capable of flight so that velocity, acceleration, force and momentum may be calculated and Newton s laws of motion may be tested. Hypothesis: Predict how the shape of the airplane, force applied, and mass will affect the calculated quantities. Part 1: 1. Choose an airplane design from those presented in the front of the classroom. 2. Fold chosen paper plane. 3. Make 2 copies of your plane (this means you will have 3 paper airplanes in total) 4. Label each plane with your group name. 5. Determine the mass of your plane. 6. Determine the mass of a paper clip. Note: You may change your design at home, but you must leave lab today with a plane folded. If you use a different design, you must use a standard piece of paper and you may not add or remove any part of the paper. Mass of Plane 1 g x 10-3 = kg Mass of Plane 2 g x 10-3 = kg Mass of Plane 3 g x 10-3 = kg Average Mass of Planes g x 10-3 = kg Mass of Piece of Paper g x 10-3 = kg Mass of Paper Clip g x 10-3 = kg

3 Part 2: Materials: Timer, meter stick, airplanes, data sheet 1. For each group, assign a pilot, recorder and a timer. 2. Report to assigned flight area where recorders will mark out a baseline. 3. Pilots will remain behind their baseline and maintain eye contact with their timers for proper synchronization of liftoff times. Press start for liftoff and stop for landing. Launch should be as uniform as possible to control force and momentum. 4. Timers should move to the right side of the start line and maintain eye contact with pilots to ensure proper start and stop times of flight. 5. Recorders should move to the left side of the start line and record measurements and observations. Recorders are responsible for the notes and observation section of the report. Recorders need to note 6. Each flight landing site should be marked with chalk using the recorders initials and trial number. After marking landing site, immediately move back to the sidelines to clear the tarmac for incoming flights. 7. Launch your airplane and record distance. Switch planes if your plane becomes hard to fly. 8. Repeat step 7 three times. 9. Switch roles, add 1 paper clip to your airplane and repeat steps 7 and Switch roles, add a second paper clip, repeat 7 and Switch roles, add a third paper clip and repeat 7 and To reduce the amount of people on the flight area, distance will be recorded after all trials are completed. All team members are required to record the distance and time data. 13. Clean up area of all paper airplanes and return all equipment.

4 Part III: Calculations. 1. Velocity: is defined as the change in distance over time, v = d /t. The units are d (meters) divided by Time (seconds). V = d (m) / t (seconds) 2. Acceleration is defined as the change of speed or direction over time. It is denoted as a = v f v i / t. Where v f (final speed) v i (initial speed) is divided by time, t (seconds). The units for acceleration are meters per second squared written as m/s 2. a = v f v i / t 3. Force = mass (kg) x acceleration (m/s 2 ). Force causes objects to move, change speed or the direction of original motion. An object moving at a constant velocity has no force other than the original force that caused it to accelerate in the first place. If acceleration is zero, then F = m x 0, which equals zero! The units of force are kg-m/s 2 or the newton (N) in honor of the author of The Laws of Motion, Sir Isaac Newton. Notice that force is related to mass and acceleration and the next derived unit, momentum is related to mass and speed. F (N) = m (kg) x a (m/s 2 ) 4. Momentum = mass (kg) x velocity (m/s). Notice how both force and momentum have a mass unit indicating the importance on mass in the overall energy or in this case the inertia that an object possesses. Although these objects possess energy we are, at this point, only referring to what it takes to begin, change or stop motion. The units for momentum are kg-m/s. There is no square on the unit for momentum. Momentum relates to speed, force to acceleration. p = m (kg) x v (m/s)

5 The Lab Report: Airplane Lab Due: * Your report must be typed. * Your report must be stapled prior to class. Checklist The format of the report should include: 1. Title 2. Your name and 3. Introduction 4. Methods and Materials 5. Results: Include your data table 6. Discussion and Conclusion 7. References Introduction The introduction should give the reader sufficient background to understand the rest of the report. This section of the report should contain APA citations from references that are used to provide the necessary background information. It should answer the following questions in this order: What knowledge already exists about this subject, and what concepts need to be addressed in order to understand the rest of the report? What is the specific purpose of the study? What is the hypothesis? It might include general figures (include captions and references). Methods and Materials The procedure used in the experiment, along with the materials used should be reported in this section. This section should be written in the past tense. Do not use I or We and do not repeat my procedure. Results Staple your data table of data and calculations- remember- neatness counts. You need to include the table of masses of the airplane and paper clip.

6 Discussion and Conclusion How did the mass of the plane affect the velocity, acceleration, force and momentum of the plane? Was this trend consistent with your hypothesis.? References This section lists all resources used in the report and must follow APA format.