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NameDateMotionSection 3 AccelerationScan Use the checklist below to preview Section 3 of your book. Read all section titles. Read all boldfaced words. Read all graphs and equations. Look at all the pictures and read their captions.ReviewVocabulary Define velocity in a sentence to show its scientific meaning.velocityStudent responses will vary. Sentences should include speedand direction.NewVocabulary Use your book to define the terms below.centripetal accelerationrate of change in velocityacceleration of an object toward the center of a curved orcircular pathAnalyze why we say an object is accelerating, when we usuallymean that it is speeding up. An object that is slowing down also isaccelerating.In the everyday sense, acceleration implies increasing in speed.In the scientific sense, it describes changing velocity—increasingor decreasing speed, or changing direction.AcademicVocabulary Use a dictionary to define constant to its scientific meaning.constant24 Motionnot varying or changing over time; a quantity that does not varyCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.acceleration

NameDateSection 3 AccelerationVelocity andAccelerationI found this informationon page.SE, pp. 57–58RE, p. 36(continued)Synthesize Create a graph titled “Speed Changing Over Time” toshow the acceleration of the car traveling around your course(above). Place the labels A, B, C, and D along the horizontal axis torepresent the time when the car travels each part of the course. Draw a line on the graph to show how the speed of the carchanges with time. Label each of the four parts of the graph with either a plus sign,a minus sign, or a zero to indicate where the car’s acceleration isSpeed Changing Over Timepositive, negative, or zero.Speed Changing Over TimeSpeedAccept all reasonableresponses.0Copyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.123045 6Time78910min Describe the relationship between speed and acceleration asshown in your graph.Acceleration is positive when speed is increasing, negative whenspeed is decreasing, and zero when speed is constant.Motion inTwo DimensionsI found this informationon page.SE, pp. 58–60RE, pp. 36–37Compare the results of applying the acceleration equation inthe following two cases: (1) an object that goes from 0 to 10 m/s in4 s, and (2) then goes from 10 m/s to 30 m/s in 8 s.(1) a (vf – vi )/t (10 m/s 0 m/s)/4 s(2) a (vf vi )/t2 2.5 m/s2 (30 m/s 10 m/s)/8 s 2.5 m/sThe results are the same. Calculations show that if an object wentfrom 0 to 10 m/s in 4 s and continued the same acceleration, itwould go from 10 m/s to 30 m/s in another 8 s.Motion25

NameDateSection 3 Acceleration(continued)Analyze why the SI unit of acceleration is m/s 2.Acceleration is final velocity minus initial velocity, divided by time.The difference of two velocities, with SI units m/s, also must haveunits m/s. If this difference is divided by time, with SI unit s, theresult has the units m/s/s, or m/s2.I found this informationon page.SE, p. 59RE, p. 38Circular MotionI found this informationon page.SE, p. 59RE, p. 38Model a ball thrown horizontally.Sketch the path of the ball and drawarrows showing its horizontal andvertical velocity at three points alongthe path. Vary the length of yourarrows to show the magnitude of thevelocities.Create a top view of an objectVelocitymoving in a circle at constant speed,such as a ball on a string. Show atleast two positions of the object. AtCentripetalaccelerationeach position, draw an arrow for theobject’s velocity and another arrowfor the centripetal acceleration of theVelocityobject.S YNTHESIZE I TDistinguish between average acceleration andinstantaneous acceleration. Be sure to explain how the acceleration equationcalculates average acceleration, instantaneous acceleration, or both.Average acceleration describes the acceleration of motion when acceleration is changing.Instantaneous velocity is the total change in velocity divided by the total time of travel.Instantaneous acceleration describes the acceleration of motion at a given point in time.The acceleration equation defines average acceleration, because it is the change invelocity, or vf – vi , divided by the time traveled.26 MotionCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.Projectile Motion

NameDateTie It TogetherMotionUse this activity with page 25.Draw a closed racecourse with parts labeled A, B, C, and D, wherethe following occurs: [Hint: the path can cross itself once.]A. The car is speeding up while traveling in a straight line.B. The car is curving left at constant speed.C. The car is traveling in a straight line at a constant speed.D. The car is curving right while slowing down.DBACopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.CAccept allreasonableresponses.A figure-8 trackis thesimplest answerbut not the onlypossible one.Use your book to place the terms distance, displacement, speed,and velocity in the table below.Does not involve InvolvesdirectiondirectionUnits do not involve time distancedisplacementUnits involve timevelocityspeedMotion27

NameMotionDateChapter Wrap-UpNow that you have read the chapter, think about what you have learnedand complete the table below.1. Write an A if you agree with the statement.2. Write a D if you disagree with the statement.After YouReadMotion Distance and displacement are the same thing.DSE p. 45RE p. 27 Velocity and speed are the same thing.DSE p. 50RE p. 30 Whenever an object accelerates, its speed ordirection changes.ASE p. 53RE p. 34Compare your previous answers to these.ReviewUse this checklist to help you study.Study your Science Notebook on this chapter.Study the definitions of vocabulary words.Review daily homework assignments.Re-read the chapter and review the charts, graphs, and illustrations.Review the Self Check at the end of each section.Look over the Chapter Review at the end of the chapter.S UMMARIZE I TAfter reading this chapter, list three things you havelearned about motion.Accept all reasonable responses.28 MotionCopyright Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.Review the information you included in your Foldable.

Motion Chapter Wrap-Up Now that you have read the chapter, think about what you have learned and complete the table below. 1. Write an A if you agree with the statement. 2. Write a D if you disagree with the statement. Name Date Compare your previous answers to these. Review Use this checklist to help you study.