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Forces Affecting Objects Acknowledgments The Teaching & Learning Collaborative (TLC) gratefully acknowledges the help and advice of the following individuals in the writing of Science Tasks with Otis & Flask: • Diane Cantrell, Science Education Consultant • Kathy Colasanti, Director of Curriculum, Buckeye Valley Local Schools • Carol Damian, Science Teacher Leader, Worthington City Schools • Chris Doolittle, Curriculum Coordinator, Westerville City Schools • Cindy Roepke, Curriculum Coordinator, Pickerington Local Schools • Eydie Schilling, Director of Curriculum and Instruction, Granville Exempted Village Schools • Jennifer Ullman, Teacher on Special Assignment, Science, Dublin City Schools • Pat Barron, Founding Director and Project Manager, Teaching & Learning Collaborative • Kelli Shrewsberry, Director, Teaching & Learning Collaborative The Collaborative also thanks the many teachers and students who participated in field- testing the Centers and provided important feedback. Finally, thanks to the staff of Attaché and of Baesman Printing, Maureen Looker and Bev May of the TLC staff, and Catherine Behrends for the production of this booklet. About the Teaching & Learning Collaborative TLC is a non-profit organization whose mission is to improve science and mathematics education. It is a coalition of school districts, organizations, businesses and government agencies with whom we collaborate to design and carry out our work. The TLC works at a variety of levels, from the classroom to the state level, to ensure that all students have access to quality education in science and mathematics. Currently, our work is focused in three areas: • Professional development in science and mathematics for grades K-12 educators • Special initiatives • Tailored contracted professional services © Copyright 2008 by the Teaching & Learning Collaborative Science Tasks with Otis & Flask cannot be copied or reproduced by any means without written permission of the Teaching & Learning Collaborative except for pages indicated for student use, which may be reproduced yearly without written permission for educational use in a single classroom in conjunction with any of the activities contained in Science Tasks with Otis & Flask. Forces Affecting Objects TEACHER INFORMATION FORCES AFFECTING OBJECTS TEACHER INFORMATION Teacher Information Center Summary This booklet consists of three centers and their associated readings and assessments. Center 1 – Ramp Rolling/Gravity & Collision involves observing the effect of the non-contact force of gravity and the contact force of collision on the motion of a toy car when rolled down a ramp. Center 2 – Get Pushy examines the impact of a push on the toy car as it rolls down the ramp. Center 3 – Magnetic Fishing explores how magnetism can be both a contact and non- contact force. This Center also includes a Final Assessment that the teacher will use to check students’ understanding from all three centers. Teacher Directions For Setting Up The Centers Materials: Center 1 - Ramp Rolling/Gravity & Collision and Center 2 - Get Pushy The following materials are for one station set up. To accommodate more students, mul- tiple stations can be used. • Toy car (“Hot Wheels” type) • Long (at least 3’) wood, plastic, or foam board ramp (Note: Instead of using a board, you can prop up one end of a long table to form a ramp. Use a box on the floor to catch the car as it rolls off the table-ramp) • Stopwatch or similar timer (if not available, use a clock with a second hand) • 6 books (each 1” or so thick) to help make a ramp, and later, a barrier • 1 copy per student of the Student Packet • 1 copy of the Answer Key • 1 copy of the Student Task Cards Setting Up Centers 1 and 2 • Provide materials as listed above • Make 1 copy of the Task Card. Optional: Laminate it and /or glue it to a file folder or other stiff material to make it stand up • Make 1 copy per student of the Student Packet • Make 1 copy each of the Answer Key. Make these accessible to students but hid- den from view. Optional: Laminate each answer sheet and glue/place each in a file folder marked “Answer Key” © 2008 Teaching & Learning Collaborative - Science Tasks with Otis & Flask. All rights reserved. T-1 TEACHER INFORMATION FORCES AFFECTING OBJECTS Materials: Center 3 - Magnetic Fishing • Small circular magnets with a hole in center • String (for the fishing-pole line), approximately 5” long • Ten paper “fish” (patterns are at the end of this section and a full color version is in the “Additional Materials” envelope) • Steel paper clips to attach to fish (so they’ll be attracted to the magnetic fish line) • 1 copy per student of the Student Packet • 1 copy of the Answer Key • 1 copy of the Task Card • Unsharpened pencil or wood ruler to tie the string to (the part of the “fishing pole”) • Clear tape (to attach paper clips to fish) • The Answer Key/Rubric for the Final Assessment which the Teacher grades. It is at the end of the Teacher Information Section. Setting Up Center 3 • The fishing pole and the magnetic fish should be pre-assembled for the magne- tism activity and placed at the activity center. (Tie the string to the pencil or ruler to make a “handle and fishing line”. The fishing line and magnet should be about 3” long. Tie the magnet to the opposite end of the string to make a “fishing hook”. Tape a steel paper clip to the back of each of the 10 fish.) • Make 1 copy per student of the Student Packet • Make 1 copy of the Answer Key. Make these accessible to students but hidden from view. Optional: Laminate each answer sheet and glue/place each in a file folder marked “Answer Key”. • Make a copy of the Task Card. Optional: Laminate it and /or glue it to a file folder or other stiff material to make it stand up. Content Reviewed These three centers address several aspects of the effect of forces on the motion of objects. Both the types of forces and the predicted changes in motion are included. A force can stop something from moving, start moving or change speed or direction. Forces can be divided up into contact (touching) forces and non-contact (not touch- ing) forces. Some forces are usually one or the other, while other forces may be both. For example, gravity is an excellent example of a non-contact force. Gravity causes objects to fall down without any direct contact. Even when gravity holds an object down (like a ball resting on the ground) the contact is between the ball and the Earth. It is Earth that causes the gravitational force that holds the ball down. The force of collision is one example of a contact force. When two objects collide, the force occurs when the objects actually touch each other. Friction is another example of a con- T-2 © 2008 Teaching & Learning Collaborative - Science Tasks with Otis & Flask. All rights reserved. FORCES AFFECTING OBJECTS TEACHER INFORMATION tact force. Magnetic Force is an example of a type of force that can be either a contact or non-con- tact force. You can use a magnet to move an object without touching it. However, when a magnet picks up and holds an object it is exerting a contact force. The other content addressed in these centers is the idea of being able to predict how the motion of an object will change when the object experiences a force. Center 2 uses the change in speed of a car when it is pushed with a different force as an example. Other ex- amples would be a baseball being hit with a bat, pulling an object such as sled, or having a soccer ball slowly roll to a stop because of friction. Prerequisite Skills Students will need the following skills to do the activity: • Ability to set and read a stopwatch or similar timer. • Ability to scientifically describe and sometimes explain orally and in writing (in- cluding pictures) what they have observed. Vocabulary Non-contact force: A force that acts on an object without touching the object (e.g., magnet and gravity). Contact force: A force that acts on an object by touching the object (e.g., collision, magnets and gravity). Gravitational force: A force between two or more masses (such as the Earth and a person); it is always an attracting force. Speed (of falling objects): How fast an object is moving downward. Non-contact magnetic force: A magnetic force that acts on objects at a distance, without having to touch the object. Contact magnetic force: A contact force exerted on ferro-magnetic objects by the magnet (attracted to the magnet). Attract: To bring or pull toward (not away). Repel: To push away (not attract). © 2008 Teaching & Learning Collaborative - Science Tasks with Otis & Flask. All rights reserved. T-3 ANSWER KEY FORCES AFFECTING OBJECTS Answer Key Check Your Understanding Final Assessment Answer: Teacher grades Name one contact and one non-contact force that you observed during these activi- ties. Describe how each force affects the motion of an object. Forces and their descriptions that might be named are: Gravity As a non-contact force, it makes objects fall or roll down a hill or ramp without having direct contact. Magnetism As a non-contact force, it attracts and causes certain metals and objects to move without actually touching them (like the paperclips in Magnetic Fishing). As a contact force, it stops the motion of certain metals and other objects when they are held by the magnet (like when the paperclips were held touching the magnet). Collision A contact force that can start, stop, speed up, slow down or change the direction of the motion of an object when it acts upon the object by coming in contact with it. Push, Pull Any force is defined as a push or pull.
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