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Name: Unit 3 - Motion Chapter 9: Acceleration DAY OUTLINE DATE 1 Ch.8 Test Read 9.1 summaries pg. 164-165 Assignment: Velocity & Acceleration WKS Positive,_Negative_and_Zero_Acceleration 9.1 Notes 1.

1 Name: Unit 3 - Motion Chapter 9: Acceleration DAY OUTLINE DATE 1 Ch.8 Test Read 9.1 summaries pg Assignment: Velocity & Acceleration WKS Positive,_Negative_and_Zero_Acceleration 9.1 Notes 1. Change in Velocity. Acceleration Assignment: TQ pg. 391 #1,3,8,9 Calculating Change in Velocity WKS 3. Deceleration Quiz 4. Velocity-time graph 9. Notes (slides 1-5) 5. Constant Acceleration Assignment: TQ pg. 405 #11-13 Describing Motion WKS 4 9. Notes (slides 6-9) 6. Gravity Assignment: Calculating Acceleration WKS 7. Acceleration due to Analyzing Velocity-time Graphs WKS Motion Match Up WKS 5 Acceleration Lab 9-D pg Ch.9 Review: Ch.9.1 & 9. Assessment WKSs Ch. 9 Review pg #4,6,7,11-14,16-1 Physics_Unit WKS 7 Unit 3 Review: pg #4, 8-1, 14, 18-0, 4-6, 9, 31-33, 36-_51 8 Unit 3 Test (Ch.8 +9) Chapter 9 Key Terms due gravity 8. Air resistance

2 Chapter 9: Acceleration KEY TERMS Key Term Definition Example Change in velocity Acceleration Deceleration Velocity-time graph Constant acceleration Average acceleration Gravity Acceleration due to gravity Air resistance

(negative) Q continued Reading Check. What is the acceleration ofaiiobjecttravellingata constant vehiciy 164 MHR Section 9.1 DescrIbing Acceleration 0 woe McG.,aw-HiO liyeson i.

Explain your answer on the lines below. How do signs Indicate changes in acceleration? Recall that forward motion is defined as positive and backward motion is defined as negative.

have learned. Repeat the quiz until you get alt the answers correct. How can you calculate a change in velocity?

3 (negative) Q continued Reading Check. What is the acceleration ofaiiobjecttravellingata constant vehiciy 164 MHR Section 9.1 DescrIbing Acceleration 0 woe McG.,aw-HiO liyeson i.atited 000 McGraw4l Ryueon lirmed Section 9.1 DescrIbing Acceleration MHR 165 Describing Acceleration Textbook pages Before You Read Are you accelerating if you are slowing down? Explain your answer on the lines below. How do signs Indicate changes in acceleration? Recall that forward motion is defined as positive and backward motion is defined as negative. Different factors can help you decide if an object s acceleration is positive or negative, as shown in the table below: A Create a Quiz NAft have read this IfliTFve opestion qutz based on what you have learned. Repeat the quiz until you get alt the answers correct. How can you calculate a change in velocity? A change in velocity () occurs when the speed of an object changes, or its direction of motion changes, or both. Changes in velocity can be either positive or negative. To find a change in velocity, subtract the initial velocity () from the final velocity (i,). = 1w V1 V1 How do signs indicate changes in velocity? North, east, up, and right are considered positive ( ) and south, west, down, and left are negative ( ). If you slow down from 9 ni/s forward (positive) to m/s forward (positive), your change in velocity is as follows: 1w = = + rn/s (+9 m/s) = 7 m/s Your change in velocity is 7 ni/s opposite the forward motion. Your initial forward direction is positive, so your change in velocity is negative when you slow down. Factor Velocity Acceleration hicrease in speed while travelling forwad, osiive) + + (positive) e.g., acceleratng after you have stopped at a stop sign decrease in speed while apply travelling forward, e.g., + (positive). (negative) Ing the brakes on a bicycle - - increase hi speed while (negative) travelling backward, e.g., a ball talhng to earth no change in speed, constant 0 e.g., running at a constant speed Note that an object that is slowing down is changing its velocity; therefore, it is accelerating. Acceleration in a direction that is opposite the direction of motion is sometimes called deceleration. 0 Reading Check 1. Define acceleration. What is acceleration? Acceleration is the rate at which the velocity of a moving object changes. A change in velocity can be a change in either speed or direction. Thus, acceleration occurs when the speed of an object changes, or its direction of motion changes, or both. Acceleration is a rate of change. This means it also takes into account how quickly the velocity changes. 0

.... when (1ir1 rv. 166 MI-In Section 9.1 Oeecnbing Acceleration C 600 McG,aw-HC ftyfl 168 MI-IR Section 9.1 Describing Acceleration 0008 MoGraw-fIS Ryarson Lfrtted Use with textbook pages 380-386.

Activity Name eiid Use with textbook page 385-386. Positive, negative, and zero acceleration Interpreting Illustrations ij j 1.

4 .... when (1ir1 rv. 166 MI-In Section 9.1 Oeecnbing Acceleration C 600 McG,aw-HC ftyfl 168 MI-IR Section 9.1 Describing Acceleration 0008 MoGraw-fIS Ryarson Lfrtted Use with textbook pages Velocity and acceleration Vocabulary constant velocity positive acceleration deceleration same direction ne9alive speed negative acceleration vector opposite direction velocity positive Cloze Dale Activity Name eiid Use with textbook page Positive, negative, and zero acceleration Interpreting Illustrations ij j 1. In each situation described below, identify whether the object or person has positive acceleration, negative acceleration, or zero acceleration. a) an aiiplane taking off b) a person standing still at a bus stop flete c) a bus braking as it approaches a red light Use the terms in the vocabulary box to fill in the blanks. You may use each term only once, 1. Since velocity is a it is dependent on the of the object and the direction in which the object is moving.. A change in velocity is when an object speeds up. 3. A change In velocity is. an object slows down. 4. An object has when it is travelling with uniform motion. 5. Acceleration is the rate of change in 6. An object has a when its speed is increasing. 7. An object has a when its speed is decreasing. 8. If an object s acceleration is in the as its velocity, the object s speed increases. 9. If an object s acceleration is in the as its velocity, the object s speed decreases. 10. Acceleration that is opposite to the direction of motion is called d) a person sliding down a water slide with constant velocity. In each illustrated example shown below, identify whether the object or person has positive acceleration, negative acceleration or zero acceleration. c). 1-0mb +6mb -._.: e) acclerstlan acceleration velocity :. tate tls t=ls t 3s t4s? t,s s hi d) 4= 4mlo f) - 0cm 0cm 40cm 60cm SOon too cm rjl

5 9.1 Describing Acceleration Student Notes An object travelling with has equal displacements in equal time intervals. An object travelling with non-uniform motion will: have different during equal time intervals. take different to travel equal displacements. have a continuously Changes in Velocity A change in velocity() occurs when the of an object changes, or its changes, or both. Achangein can be calculated by: A = If the change in velocity is the object is travelling with Positive Changes in Velocity If the change in velocity is the (+, -) as the initial velocity, the speed of the object is Example: A = = Negative Changes in Velocity If the change in velocity is the object is Example: z = S + 9m!s - (+6mIs) = + 3m/s = +mis - (+9mIs) = -7m!s (+, -) of the initial velocity, the speed of the Acceleration isthe the change in can be due to a change in a change in or both. two objects with the can have > this is because acceleration describes Example: Suppose both of these vehicles, starting from rest, speed up to 60 km/h. They will have the but since the dragster can get to 60 km/h faster than the old car, the

Positive Acceleration The is the same as the acceleration velocity Example#l: A car in the direction.

Negative Acceleration Acceleration that is the direction acceleration of motion is sometimes called Example#l: A car in the > If we designate the forward direction as

* Example#3: A in the direction. > If we designate the backward direction as then the change in velocity is though the car is increasing its speed.

6 Positive Acceleration The is the same as the acceleration velocity Example#l: A car in the direction. > If we designate the forward direction as (+) then the change in velocity is therefore the acceleration is (+). Negative Acceleration Acceleration that is the direction acceleration of motion is sometimes called Example#l: A car in the > If we designate the forward direction as (+) then the change in velocity is therefore the acceleration is Positive and Negative Acceleration *Remember positive (+) and negative (-) refer to directions.* Example#3: A in the direction. > If we designate the backward direction as then the change in velocity is though the car is increasing its speed. therefore the acceleration is negative (-) even L =Vf =( 4m!s) ( lm/s)= 3m/s = = 4 mis rn!s [; e Example#4: A in the direction. > If we designate the backward negative (-) then the positive (+), therefore the is positive (+) even though the car is Av=vf v=( lm/s) ( 4m/s)=-f-3m/s= Vf = ImIs its speed. = 4mIs

Applying Name Date Knowledge Use with textbook page 38. Calculating change in velocity 1. Complete the following table by calculating the missing quantities.

7 Applying Name Date Knowledge Use with textbook page 38. Calculating change in velocity 1. Complete the following table by calculating the missing quantities. Positive (-i-) represents the forward motion. Use the formula L=. In the last column, describe the change in velocity (e.g. object is slowing down, object is speeding up, or object is in uniform motion). Description of L + 14 rn/s + 5 rn/s object is slowing down +8m/s Orn/s +5m/s +1m/s +0m/s 3Gm/s 38m/s 1Gm/s 16m/s Orn/s 3m/s rn/s. Use the following data table to calculate the change in velocity for each time interval. Suppose motion toward north is positive (+). a) Os los... Time (s) Velocity (mis) b) los 0s.. c) 0s 30s. d) 30s 40s. e) 40s 50s 008 McGraw-Hili Ryerson Limited Section 9.1 Describing Acceleration MHR 167

is slope slope acceleration) 9. Calculating Acceleration Student Notes Calculating Acceleration: The of an object depends on the the to change the velocity.

8 is slope slope acceleration) 9. Calculating Acceleration Student Notes Calculating Acceleration: The of an object depends on the the to change the velocity. When stopping a moving object, the relationship between time and acceleration is: the stopping time the stopping time the acceleration the acceleration Velocity-Time Graphs: Vefacity vs. Time The motion of an object with is best represented by a graph. The motion of an object with is best represented by a graph. 0 0 = Time (s) zf slope: _5m1s =13m1s The slope of a velocity-time graph is measured in Determining Motion from a Velocity-Time Graph: ( in the acceleration) object s velocity is direction. ( acceleration) object s velocity is ( object s velocity is in the direction or the object s velocity is increasing in the negative direction. S 0 Vefocity vs. Time During which time interval was The acceleration zero? The acceleration negative? The acceleration positive? The object increasing it s velocity north? The object decreasing it s velocity north? 0 The object moving at a constant velocity north? t t Time (s)

Calculating Acceleration: - a = (ä)(&) Lt = Example 1: A pooi ball traveling at.5 mis, towards the cushion bounces off at 1.5 mis. If the ball was in contact with the cushion for 0.

9 Calculating Acceleration: - a = (ä)(&) Lt = Example 1: A pooi ball traveling at.5 mis, towards the cushion bounces off at 1.5 mis. If the ball was in contact with the cushion for 0.0 s, what is the ball s acceleration? (Assume towards the cushion is the positive direction.) Example : A car accelerates from rest at 3.0 mis forward for 5.0 s. What is the velocity of the car at the end of 5.0 s? Example 3: A train is travelling east at 14 ni/s. How long would to increase its velocity to ni s east, if it accelerated at 0.50 mls east? (assign east direction positive (+)). More Practice: 1. A truck starting from rest accelerates uniformly to 18 ni s [W] in 4.5 s. What is the truck s acceleration?

Gravity is a. A toboggan moving 5.0 mis forward decelerates backwards at -0.40 m1s for 10 s. What is the toboggan s velocity at the end of the 10 s? 3.

6 mis Gravity and Acceleration: up tf that acts between down that move through the air.

10 Gravity is a. A toboggan moving 5.0 mis forward decelerates backwards at m1s for 10 s. What is the toboggan s velocity at the end of the 10 s? 3. How much time does it take a car, travelling south at 1 mis, to increase its velocity to south if it accelerates at 3.5 mis south? 6 mis Gravity and Acceleration: up tf that acts between down that move through the air. Ignoring air resistance, all objects will is a friction-like force that opposes the motion of objects towards the Earth at Calculating Motion Due to Gravity: Example: Suppose a rock falls from the top of a cliff. What is the change in velocity of the rock after it has fallen for 1.5 s? (Assign down as negative (-))

11 More Practice: 1. What is the change in velocity of a brick that falls for 3.5 s?. A ball is thrown straight up into the air at 14 m/s. How long does it take for the ball to slow down to an upward velocity of 6.0 mis? 3. A rock is thrown downwards with an initial velocity of 8.0 mi s. What is the velocity of the rock after 1.5 s?

Name: Block: Date: Science 10 Ch. 9. Describing Motion Assignment Example 1: The following position time graph shows an object travelling with uniform motion. 30 5 0.

12 Name: Block: Date: Science 10 Ch. 9. Describing Motion Assignment Example 1: The following position time graph shows an object travelling with uniform motion Position vs Time oo Time (s) The slope of the line is.5 mis. Since the slope is constant, the corresponding velocity time graph would be a horizontal line drawn at.5 m/s. Velocity vs Time C 00 - C. 0 4 Time(s) Describe the motion of the following velocity-time graphs. Include the direction of travel, whether the object is accelerating or decelerating, and any times where the object stops moving altogether. a. Slopes: 0-4s: e L 7 Velocity vs Time V Time(s) s: 6-8s 8-lOs:

$8 10 5 \ 0 4 6 8 10$ Time(s) Slopes: O-4s:

13 b. Velocity vs Time 1 10 Slopes: O-s: -6s: g Time (s) 6-1 Os: C. Velocity vs Time \ Time(s) Slopes: O-4s: 4-6s: 6-8s: 8-lOs: d Velocity vs Time Slope: 0-lOs: Time (s)

Applying Name Date Knowledge Use with textbook pages 396-400. Calculating acceleration 1. What is the formula for each of the following quantities?

14 Applying Name Date Knowledge Use with textbook pages Calculating acceleration 1. What is the formula for each of the following quantities? (a) acceleration (b) change in velocity (c) time interval. Complete the following table. Use the motion formula to calculate the missing quantities. Show all your work and use the correct units. Ghange in Time Acceleration Formula Used and Velocity Calculation Shown l4omjs 8s 17,5m/s 8 60 km/h 4 h 10 km/h 48 km/h 15s 1m/s.5s 3.5 rn/s 5 rn/s 1.5 rn/s 9.6h 5km/h t 3. Solve each problem using the appropriate motion formula. Show all your work and use the correct units. a) A car moving north goes from 5.56 m/s to 63.9 rn/s in 7.5 s. What is the acceleration? b) If a sprinter starts a race and has an acceleration of.4 rn/s final velocity, assuming the initial velocity is 0 m/s? in.5 s, what is his c) A rock accelerates at 9.8 rn/s velocity from 4.5 rn/s to 19.4 m/s? when falling. How long does it take to change its d) A satellite released from a stationary space shuttle accelerates to +68 rn/s 5 s. What is its change in velocity? in 17 MHR Section 9. Calculating Acceleration 008 McGraw-Hill Ryerson Umited

Name Date Analyzing Information Use with textbook pages 394-396. Analyzing velocity-time graphs 1. What is the meaning of each of the following features of a velocity-time graph?

15 Name Date Analyzing Information Use with textbook pages Analyzing velocity-time graphs 1. What is the meaning of each of the following features of a velocity-time graph? (a) the slope of the line (b) a line above the x-axis (c) a (d) a (e) a line below the x-axis line with a positive slope line with a negative slope (f) a horizontal section of the graph (g) a point where the line crosses the x-axis Use the following velocity-time graph representing the motion of a ball moving to the right on a table to answer questions and Time (s). Complete the following table. Describe the slope, ball (e.g. positive, negative, or zero). acceleration, and velocity of the MOTION OF A BALL Time Interval Slope Acceleration Velocity Os s s 6s 6s 8s 8s 1s 3. Describe the motion of the ball at each time interval. (a) 0 s s (b) s 6 s - (c) 6 s 8 s (d) 8s 1s 008 McGraw-Hill Ryerson Umited Section 9. Calculating Acceleration MHR 173

DATE: NAME; CLASS; CHAPTER g4 Motion Match-up 9 B L M31 Goal Review your understanding of terms that describe motion. Match each statement on the left with the correct term on the right.

a physical quantity that has magnitude but no direction B. acceleration due to 3. descnbes gravity how much an object s position has changed C. air resistance 4.

16 DATE: NAME; CLASS; CHAPTER g4 Motion Match-up 9 B L M31 Goal Review your understanding of terms that describe motion. Match each statement on the left with the correct term on the right. Write the term s letter in the appropriate space. You will not need to use every term. 1. motion with no change in speed or direction A. acceleration. a physical quantity that has magnitude but no direction B. acceleration due to 3. descnbes gravity how much an object s position has changed C. air resistance 4. the total length of a journey that an object takes D. average acceleration 5. describes how fast an object is moving, but not its direction E. average velocity 6. difference between initial time and final time F. best-fit line 7. the location of an object as seen by an observer G. change in velocity 8. quantity with both magnitude and direction constant 9. friction-like force acceleration mi s I. deceleration distance 11. can be a smooth curve or straight line K. gravity 1. allows us to picture or visualize motion L. velocity 13. describes the speed and direction of motion M. uniform 14. occurs when the speed of an object changes, or its direction motion diagram of motion changes, or both position 15. acceleration that is opposite to the direction of motion P. position-time graph 16. the change in an object s velocity (increase or decrease) in a Q. time given period of time R. time interval 17. rate of change in position for a time interval S. scalar 18. when an event occurs speed 19. the nse of a graph over its run 0. represented by the slope on a velocity-time graph H. J. N. o. T. sope V. displacement W. vector X. velocity-time graph Copyright 008, McGraw-Hill Ryerson Limited, a subsidiary of the McGraw-Hill Companies. All rights reserved. This page may be reproduced for classroom use by the purchaser of this book without the written permission of the publisher.

The Ass ait Name Date Assessment Name Date Use with textbook pages 38-386.

velocity 4 change in velocity Descriptor A. rate at which an object changes its velocity B. an object travelling with untorm motion in a straight line C.

17 The Ass ait Name Date Assessment Name Date Use with textbook pages Describing acceleration Match the Term on the left with tile best Descriptor on the righteach Descriptor may be used only once. Terifl, ii 1. acceleration. deceleration 3. velocity 4 change in velocity Descriptor A. rate at which an object changes its velocity B. an object travelling with untorm motion in a straight line C. acceleration in a direction that is tipo site to the direction of motion 0. diaritje that occurs when the speed of an object changes, or its direction of motion changes, or both Circle the letter of the best answer. C. the object remains at rest 0. nothing happens to the object 7. Suppose an object moving forward changes its velocity from 15 rn/s to 6 mls.what is the change in velocity? A. 1 ill/s 8.9 lu/s C. Pm/s 0.1 rn/s 8. Which of the following have an acceleration in the same direction as the object s rnotioii? 3.5 re/s least]; i=7.5 rn/s [east] t. = 45km/h [north]; i3 = 60 hot/h [north] Ill. i= 15 rn/s [right]; V = torn/s [left] A. I and II only B. I and Ill only C. 1.1 and III only 0. I. II, and iii 5. The tortoise moved slowly and steadily. The hare non quickly, then fell asleep 9. Which of the following are true about near the finish line. Identify the following acceleratlow? quantities as scalar or vector, respectively: the m/erage velocity of the tortoise during rho entire mce the acceleration of the hare during the first minutes of the race and thitt line it takes for the tortoise and the hate to flotish the race. A. vector, vector. scalar 8. -scalar, scalai vector C. vector. scalar, vector 0. scalar, vector, scalar A. I and 11 only B. I and III only 6. If the acceleration of an object is in the ii and Ill opposite direction as the velocity, which o the- following happens? A. the object speeds up 8. the object slows down I. When an objects speed is constant, the Iii. object has ante acceleration. When art object s speed is increasing, the object ties a positive acceleration When an object s speed is decreasing, the I object has a negative acceleration. C. ii and 1.11 only Use with textbook panes Calculating acc.leration Match the Descriptor on the left with the best VelocIty-lIme Graph an the right. The Velocity- rime Graphs represent the motion 0! a car head ing north. Each Velocity-Time Graph may be used only once. Descriptor -?s- I Velocity-Time Graph st..theearis acceleratog 3. The car is slowing clown car is travelling at constant velocity. 5. Acceleration is represented by the slope of a A. velocity-time graph B. posidontime graph C. distance time ctraph 0. acceleration-time graph 6. A meteor goes finra + (1 kia! to ± km/s in 0.04 s What is its acceleration? A km/s B. 30 kin/s C. 55 km/s kin/s C. DII hmei4 Ttmei,t Use the following velocity-lime graph to answer question TIrn(e) 7. Which line represents an object with the greatest acceleration? A.A LLt C.c D.L Use the following velocity-time graph to answer question St se - an > IC Thiie (s) 8. What is the object s acceleration between the time interval s and 4 a? A. +1 in/s B. +10 C. +0 m/s D /5 et 008 Mc0raw-tIW Ryersoe Limited Section 0.1 Describing Acceleration Mr-in MHR Section 9, Calculating Acceleration 0008 McGfaw-i-l8 ttyereon iimiied

the car s displacement? 1. (a) A car moves east along a highway at 90.0 km/h for I h and 15 mm. What is later? average velocity of 90 kmlh[e], what will be the displacement of the bus 4.5 h 5.

A truck travels from City A due west to City B, a distance of 10 km. The total north. It takes 4.0 h to complete the flight. What is the velocity of the airplane? 3.

18 the car s displacement? 1. (a) A car moves east along a highway at 90.0 km/h for I h and 15 mm. What is later? average velocity of 90 kmlh[e], what will be the displacement of the bus 4.5 h 5. A bus travels from City X due east toward City Y. If the bus travels at an the truck? time for the trip is two hours and fifteen minutes. What is the average velocity of 4. A truck travels from City A due west to City B, a distance of 10 km. The total north. It takes 4.0 h to complete the flight. What is the velocity of the airplane? 3. A single-engine airplane leaves an airport and flies to another airport 850 km 0(4 V (c) What is the total displacement of the car? 0(4 (b) Calculate the average velocity of the car. (a) Calculate the acceleration of the car. of 4.0 m/s in 1 s.. A car starts from rest and accelerates at a steady rate, reaching a final velocity (b) How long will it take for a person walking at 3.8 m/s north to move 15 m? Physics Unit (mo 5O O c rfkl)\0 uxx9

50 m in just 5.56 s. What was Bailey s average velocity? 7. Donovan Bailey set the world indoor track record in 1996 by running forward down) reach a velocity of 5 m/s downward?

19 50 m in just 5.56 s. What was Bailey s average velocity? 7. Donovan Bailey set the world indoor track record in 1996 by running forward down) reach a velocity of 5 m/s downward? (Hint: acceleration due to gravity is 9.8m1s 11. A rock falls from the top of a high cliff. How long would it take this rock to the acceleration of the car? accelerator. The car slows down from 90 kmlh[s] to 50 km/h{s] in 8.0 s. What is 10. As you approach a town while you are driving, you take your foot off the.... :1 de : L.a.. -. Position vs. Time 0-30 s: 10-0s: 0-lOs: Describe, using words, the motion of the elevator during the 30 s time interval. 9. The motion of an elevator is represented by the position-time graph below. rn/s. How much time does it take for this boat to cross the lake? 8. A boat travels across a 450 m lake with an average forward velocity of 5.0 a distance of 5.0 km? 6. How many seconds will it take a speedboat travelling at 70.0 kmlh[sj to cover

Unit 3 - Motion. 2. Acceleration Calculating Change in Velocity Wksht

Unit 3 - Motion. 2. Acceleration Calculating Change in Velocity Wksht Due Name: Unit 3 - Motion Chapter 9 Acceleration DAY OUTLINE KEY TERMS 1 Ch.8 Homework Booklet Due Ch.8 Test Read 9.1 summaries p.164-165 Assignment:Velocity & Acceleration Wksht Positive,_Negative_and_Zero_Acceleration