Mr. Storie 20F Science Student Package 3 in Motion

Mr. Storie 20F Science Student Package 3 – In Motion

In Motion: A Physics Unit

26 Mr. Storie 20F Science Student Package 3 – In Motion

MOTION SEARCH

A G G N F R D D X B J M V S O F T E G V G R O R D V I L P L Y F C D M Y N W J E O P I N A S X P R B F A D A H A E S T L E H E S T V Q S G S L W Q T R A M Q U O V D T A T I I Z J A X L V N B R E P B C Z L N T Y O I T R Z B H B J R L C W I I R C T V M G T F Y N O I T O M H A T T T E N R I N D R L Q O H K N X T N L Y L Y W O F N M B T E E F L M K M Z U P F H B A T G D O E W L N A V D L B E U S Y A O X W A K B I I Y I E M A S S N Y I J I P T E G G K L T T V P I H H G I M D F T E U N Q Q A T N A T I C K E R T A P E R V W D A G Z E G E R M U T N E M O M D E E L V L T N K C H X E I M P U L S E U N C U D K O S R J G H I L M E U N L E Q I T L F P J O N S P Z R G E Y J M C S F P O B X L F O F O J E U O B C B J P Z D R R E F U G G F R C A D C H R C D T U B P V O D M Y Z U Z F C Y F V O U A F E Q O I

ACCELERATION ARISTOTLE CONSTANT DISPLACEMENT DISTANCE ENERGY EXPONENTIAL FORCE GALILEO GRAVITY IMPULSE INERTIA MASS MOMENTUM MOTION NEWTON SCALAR TICKERTAPE TIME VECTOR VELOCITY

26 Mr. Storie 20F Science Student Package 3 – In Motion MOTION PUZZLE

Unscramble each of the clue words. Copy the letters in the numbered cells to other cells with the same number.

Car Crash – Who Is To Blame

A Discussion Activity:

This activity will be a group activity. Study the diagrams of the accident scene. Read the reports on the accident given by all the different individuals and the police. Based on your prior knowledge of physics decide who you think is to blame and who is telling the truth. Share this with your group members. As a group, reconstruct the crash. Be sure to provide proof based on your analysis of the accident scene and your knowledge of physics.

Analyzing the Car Crash Scene

The one the left shows a traffic scene moments before an accident is about to occur. Car A is travelling east at a constant velocity and is just about to enter the intersection. Car B is moving south with its right turn signal on and a motorcycle is close behind Car B. A skateboarder is crossing the intersection in the easterly direction. All of the individuals involved agreed that these were their positions before the collision. However, they could not remember any specifics about markings on the road.

The figure on the right shows the traffic scene moments after the accident. Each individual told their story in the accident reports that they filed at the police station.

Accident Report – Driver of Car A

"My car was travelling east at a constant velocity. As I approached the intersection the light turned green so I kept going through the intersection at the same speed. Then, I heard a loud bang and my car spun to the left carrying it into the pedestrian walkway on the perpendicular street past the skateboarder. My car ended up jumping the curb on the far side of the corner. I wasn't injured but everything took place so quickly I'm not entirely sure what happened."

Accident Report – Driver of Car B

"I was driving south on Main Street when I wanted to check the name of the next street. So I signalled and moved from the median lane to the curb lane. I don't know whether the signal lights were red or green or yellow as I was trying to read the street sign."

Accident Report – Skateboarder

"I was boarding east along the pedestrian walkway with my walkman on so I didn't hear any sounds. I wasn't paying much attention to the traffic when suddenly Car A spun into the walkway. I bailed and my board collided with the rear portion of Car A. I wasn't hurt but I don't listen to the walkman anymore when I'm riding."

Accident Report – Motorcyclist

"I was travelling south and had the green light. As Car B took the curb lane I signalled for a left turn then proceeded cautiously into the intersection to complete my turn. Car A ran a red light and was making a left turn when I collided with the front end of her car. I was thrown over the hood of the car and landed in the street. My helmet was not securely tied and it flew off my head on impact. I suffered a concussion and remained in the hospital for several days."

Police Report

Front end damage was extensive to the motorcycle. Car A had damage on the front and back fenders. The driver of car A claimed that the damage on the front end of the car was from a previous fender bender. The motorcyclist claimed that he made the damage on the front end of car A and that the skateboard damaged the rear of car A. Oil drops, skid marks, and the motorcyclist's helmet were found in the locations marked in figure 4. The driver of car A and the motorcyclist have conflicting stories concerning who was responsible for the accident. Therefore, we recommend that a "physics expert" be approached to investigate each driver's claim.

Vehicle Placement BEFORE Crash Explanation (which driver is at fault and how you know)

ANSWER THE FOLLOWING QUESTIONS ON POSITION AND DISPLACEMENT:

1. A car is sitting in position B; use position A, C and D to calculate the displacement of the car from point B. Use the front bumper of car B as your origin. Then, using a ruler, record the position in cm of positions A, C and D. What is the distance and displacement at point A, C and D?

2. The following data represent the initial (d1) and final (d2) positions of a car, bicycle, pedestrian, and skateboarder.

Car Bicycle Pedestrian Skateboarder

1 +2 m +7 m -1 m +4 m

2 +14 m +2 m +2 m -1 m

26 Mr. Storie 20F Science Student Package 3 – In Motion a. Draw a number line and label an origin as point “0”. Mark the initial position of each object above the line. b. Mark the final position of each object below the number line. c. Calculate the displacement of each object. d. What is happening? If each displacement takes place in the same period of time, write a paragraph to describe the motion of each object.

3. The dispatcher of a courier service receives a message from Truck A that reports a position of +5 after a displacement of +2. What was the initial position of Truck A? First solve the problem using a number line, and then solve the problem using an equation.

4. Two taxis are traveling along a Highway in opposite directions. Taxi A changes its position from +6 to +10 during the same time as Taxi B moves from +6 to +1. Draw a diagram to show the initial and final positions of each taxi.

5. Calculate the displacements of each taxi in question #4.

6. What can you conclude about the speed of the taxis?

7. How would the position of the taxis change if you decided to move your origin? How does the displacement of the taxis change if you decide to move your origin?

Formula Manipulation

1. Find the student’s total displacement for the entire trip.

2. What was his total time for the entire trip?

3. What was his average velocity for the entire trip?

4. What was the student’s total distance for the entire trip?

5. What was his average speed for the entire trip?

6. What are some of the differences between velocity and speed?

ANSWER THE FOLLOWING QUESTIONS ON SPEED, DISTANCE AND TIME:

1. April and Ashleigh run a 100-m race. April finishes the race in 13.25 s and Ashleigh takes 13.50 s. What is the average speed with which April and Ashleigh each run the 100 m?

2. Matt skateboards at 3.25 m/s for 55.0 s. How far did he travel?

3. Edward rollerblades around Assiniboine Park. He skates at 7.75 m/s for 12.5 minutes. a. How many seconds was he skating? b. How far did he skate?

4. Edgar travels to a shopping mall at an average speed of 28.0 km/h. The mall is located 8.00 km from Edgar’s home. How long in hours does it take Edgar to travel from his home to the shopping mall?

5. A ladybug is crawling across the floor in a straight line at 1.25 cm/s. The ladybug crawls 3.25 m. a. What distance in cm does the ladybug crawl? b. How long does the ladybug take to crawl this distance?

6. You and your family are traveling from Brandon to Winnipeg. The distance is 200 km. If you travel at an average speed of 105 km/h, how long will it take to travel to Winnipeg?

7. When you get to Winnipeg, you stop for lunch. This takes one hour. You then travel from Winnipeg to Thunder Bay, a distance of 385 km, in 3.75 hours. What was your average speed?

8. a. What is the total distance of your trip from Brandon to Thunder Bay? b. How long did it take you and your family to travel? (Hint: state the total time, including while you were eating.) c. What was your average speed for this whole trip from Brandon to Thunder Bay?

COMPLETE THE FOLLOWING QUESTIONS ON THE DIFFERENCE BETWEEN SPEED, VELOCITY, DISTANCE AND DISPLACEMENT.

1. For each of the following cases, calculate the average velocity (size and direction). A sketch or diagram may help.

a. A bicycle travels 36 km east in 1.2 h. b. A person runs 17 m south toward a bus stop in 2 seconds. c. A car moving west passes 6 telephone poles, each spaced 50 m apart, in 18 seconds. d. A toy car moves along a track from +2 cm to +26 cm in 0.5 seconds.

Questions #2-5 use the information below.

A city block is laid out in a grid running in the North-South and East-West directions. The blocks measure 135 m in length in the East-West direction, and 45.0 m in width in the North-South direction. A city block is drawn below.

2. On your bicycle, you travel from A to B during 9.00 s. a. What is your average speed? b. What is your average velocity?

3. If you travel from A to B to C to D, what is your a. distance traveled? b. displacement?

4. If the journey in #3 took 55.0 s, calculate a. your average speed. b. your average velocity.

26 Mr. Storie 20F Science Student Package 3 – In Motion 5. You travel around the block in 90.0 s. Calculate your average speed and your average velocity.

6. Kevin is warming up for the basketball game. He does 3 laps around the gym. Each lap is 75.0 metres. It takes 42.8 seconds for Kevin to run the 3 laps. a. What distance did Kevin run? His displacement? b. What was his average speed? His velocity?

COMPLETE THE FOLLOWING QUESTIONS BEFORE THE NEXT CLASS:

A student is walking EAST through the mall. The following table gives the position of the student at various times. The position is measured from in front of one store to a store near the EAST end of the mall.

Time (seconds) Position (metres [E])

a. Draw a rough P-T graph next to the data table. b. Calculate the distance and displacement walked by the student.

c. Calculate the average speed and average velocity of the student.

2. Jim lives on the same street as his school. The front of the school is located 1020 m [E] of Jim’s house. If Jim walks at 3.00 m/s [E], calculate the time it takes Jim to walk from his house to the front of the school.

3. An airplane flies at a velocity of 215 km/h [W] for 2.75 hours. What is the displacement for this journey?

ANSWER THE FOLLOWING QUESTIONS OF MOTION:

1. A worried student is waiting to see the principal. He paces back and forth in the hallway in front of the principal’s office. The hallway runs north and south. The door to the office is the origin, 0m. Here is a description of the student’s motion.

The student starts at 5.0 m [N]. He walks to the south for 7.0 m during 10.0 s. He stands still for 5.0 seconds. He turns around and walks 15.0 m [N] during 15.0 s. He stops to say “Hello” to a friend and remains still for 10.0 s. Finally, the principal calls him to the office door. It takes the student 10.0 s to reach the door.

a. Plot a position- time graph. Use straight-line segments to join the points.

b. What is the total time the student spent in the hallway?

c. What was the distance traveled by the student during his pacing?

d. What was the average speed of the student during his pacing?

e. What is the total displacement for the student’s journey? Find this from the graph by comparing his final position to his initial position.

f. What is the average velocity for the whole journey?

2. Find the missing information and fill in the blank spaces in the table.

26 Mr. Storie 20F Science Student Package 3 – In Motion Use a (+) sign to indicate forward movement and a (-) sign to indicate backward movement.

Change in Position (cm) Change in Time (s) Velocity (cm/s) - 20 cm 5 s 13.0 s +52.0 cm/s +50 cm +5 cm/s - 120 cm 10 s 18 s -3.0 cm/s Describing Position-Time Graphs

A. ______

B. ______

C. ______

26 Mr. Storie 20F Science Student Package 3 – In Motion D. ______

E. ______

F. ______

G. ______

Using Graphs to Determine Acceleration

Goal: Use a position-time graph to draw a velocity-time graph and determine acceleration.

Answer the questions and do the work in the space provided.

1. Use the data in the following table to draw a position-time graph. Connect the points with a smooth curve.

Time Position (s) (m) 0 +12.5 1 +8.0 2 +4.5 3 +2.0 4 +0.5 5 0.0

2. Is the object accelerating?

3. How do you know?

4. What is the sign (+ or -) of the acceleration?

COMPLETE THE FOLLOWING QUESTIONS ON KINEMATICS:

3. Find the missing information and fill in the blank spaces in the table. Use a (+) sign to indicate forward movement and a (-) sign to indicate backward movement.

Change in Position (cm) Change in Time (s) Velocity (cm/s)

- 20 cm 15 s

18.0 s +42.0 cm/s

+30 cm +25 cm/s

- 125 cm 10 s

48 s -3.0 cm/s

4. What is the difference between the terms uniform and non-uniform motion when discussing position, velocity, and acceleration.

5. Answer the following questions with formulas:

a. You drive from home to work to drop off some papers, then return home. The whole trip is 13.2 km long and it takes you 20 minutes. Calculate your speed and velocity for this journey. (40 km/h, 0)

b. A car increases its velocity from 0 km/h to 120 km/h in 10 minutes. What is acceleration? (706 km/h2)

c. A truck travelling west at 20 m/s pulls out to pass another vehicle that is moving at a constant velocity. The truck increases its velocity to 25 m/s in 2 seconds. What is acceleration? (2.5 m/s2)

d. A train crosses a boulevard at 10 km/h and begins accelerating as it heads out of the city. It crosses another road at 90 km/h as it leaves the city. If the train accelerates at a rate of 160 km/h2, how long did it take it to leave the city? (0.5 h)

6. Using the graphic below, describe the motion of the van:

a. What is the sign of the velocity? b. What is the sign of the acceleration? c. Sketch the lines for the P-T graph

26 Mr. Storie 20F Science Student Package 3 – In Motion a. What is the sign of the velocity? b. What is the sign of the acceleration? c. Sketch the lines for the P-T graph

a. What is the sign of the velocity? b. What is the sign of the acceleration? c. Sketch the lines for the P-T graph

7. Time (s) Velocity (m/s) What is the sign of the velocity? 0 + 10 1 + 9.0 What is the sign of the acceleration? 2 + 8.0 3 + 7.0 What is the acceleration over 0-5 seconds? 4 + 6.0 5 + 5.0 Describe the motion of this object?

Time (s) Velocity (m/s) What is the sign of the velocity? 0 - 4.0 1 - 8.0 What is the sign of the acceleration? 2 - 12.0 3 - 16.0 What is the acceleration over 0-5 seconds? 4 - 20.0 5 - 24.0 Describe the motion of this object?

Time (s) Velocity (m/s) What is the sign of the velocity? 0 - 11.0 What is the sign of the acceleration?

26 Mr. Storie 20F Science Student Package 3 – In Motion 1 - 9.0 2 - 7.0 What is the acceleration over 0-5 seconds? 3 - 5.0 4 - 3.0 5 - 1.0 Describe the motion of this object?

2 Reaction distance: dR = v ∆t Braking distance: dB = k v

Total stopping distance = dR + dB

1. Name and describe the three factors that influence a driver’s reaction time.

2. If your reaction time doubles what will happen to your reaction distance.

3. You are driving on a side road that is not paved. There is a sign that indicates the frictional constant of the surface is 0.12. How does this information help you drive safely?

4. a. Calculate reaction distance for a car travelling at 100 km/h or 27.8 m/s. Driver reaction time is 1.45s.

b.Calculate the braking distance for this car on wet pavement. The frictional constant is 0.10.

c. Calculate the stopping distance.

5. Compare the braking distance for a car travelling at 30 km/h (8.33 m/s) and 60 km/h (16.7 m/s) on dry pavement. What can you conclude about doubling the speed?

6. Calculate the total stopping distance for a car that is travelling at 16.7 m/s (about 60 km/h) on a rain- soaked concrete road (use 1.5 seconds as the driver’s reaction time).

7. Calculate the total stopping distance for a car that is travelling at 29.2 m/s (about 105 km/h) on a dry pavement road (use 1.5 seconds as the driver’s reaction time).

8. Calculate the total stopping distance for a car that is travelling at 29.2 m/s on a snowy road (use 1.5 seconds as the driver’s reaction time).

9. Should cell phone use by drivers of cars be banned? What about eating while driving?

10. A pedestrian wearing dark clothing at night is only visible at a distance of about 35 m to a driver using low beams. Calculate the maximum speed a car could have so that a driver could brake and avoid a collision (use a 1.5 second reaction time). Assume you are driving at speeds typically used in the city (60 km/h).

11. If two cars are moving at 60 km/h on dry pavement, how far behind must the second car travel for it to be able to stop safely and avoid ramming into the back of the first car?

Find YOUR reaction tme: http://www.bbc.co.uk/science/humanbody/sleep/sheep/reaction_version5.swf

ANSWER THE FOLLOWING QUESTIONS ON INERTIA AND FORCE:

1. Explain why a person wearing a cast on one leg becomes more tired than usual by the end of the day.

2. Suggest reasons why large vehicles such as vans and trucks tend to have larger engines and higher rates of fuel consumption than smaller and more compact cars.

3. Explain why small rabbits can often escape bigger and faster bobcats in pursuit by zigzagging as they run.

4. Predict when serious injuries are more likely to occur: when a car crashes into a large tree or into a wooden fence.

MOTION LAB – FORCE, MASS, ACCELERATION:

Complete the following question regarding the stick man on the bike:

1. If the bike is standing still and all forces acting on the bike are balanced would you describe the motion of the bike as uniform or non-uniform?

2. What kind of motion is shown by the bike if a constant unbalanced force (he begins to peddle) acts on the bike to move it forward – uniform or non-uniform?

3. How does the direction of the unbalanced force and the direction of motion compare?

4. What is the effect on the motion of the bike if you increase the unbalanced force acting on the bike (peddling harder) while keeping the mass constant?

5. How would the acceleration of the bike change if the mass of the passenger increased (doubling on the handle bars) while the force was kept constant?

6. As you increased the mass of the bike (added more people), what must you do to keep the acceleration constant?

7. If you made a graph of acceleration and mass, what would it look like? What would be the relationship between the two?

MOTION LAB – FORCE, MASS, ACCELERATION:

2 Force Mass Distance (m) Time (s) Vave (m/s) Aave (m/s ) 1 – pushing Chair +10 m 1 – pushing Chair + 1 +10 m 1 – pushing Chair + 2 +10 m 2 – pushing Chair + 2 +10 m 3 – pushing Chair + 2 +10 m

COMPLETE THE FOLLOWING QUESTIONS REGARDING THE LAB:

a. What kind of motion is shown by the chair if the unbalanced force acting on the chair is 0 Newtons?

b. What kind of motion is shown by the chair if a constant unbalanced force acts on the chair?

c. How does the direction of the unbalanced force (pushing on the chair) and the direction of motion compare?

d. What is the effect on the motion of the chair if you increase the unbalanced force acting on the chair (more pushers) while keeping the mass constant?

e. How did the acceleration change as the mass increased while the force was kept constant?

f. If you made a graph of acceleration and mass, what would it look like? What would be the relationship between the two?

g. As you increased the mass of the chair (added more people), what must you do to keep the acceleration constant?

ANSWER THE FOLLOWING QUESTIONS ON NEWTON’S 3RD LAW:

1. In each of the following cases, sketch the situation and label the action-reaction pairs.

a. A fish swims.

b. A hockey player takes a slapshot.

2. While driving down the road, a mosquito collides with the windshield of your car. Which of the two forces is greater: the force that the mosquito exerts on the windshield, or the force that the windshield exerts on the mosquito?

3. Two students are facing each other while standing on their skateboards. One student throws a mass (such as a medicine ball) to the other student. Describe what happens in terms of force and motion.

4. In terms of action-reaction force pairs, explain why it is important to use helmets, elbow pads, knee pads, and other protective clothing when using skateboards or in-line skates.

ANSWER THE FOLLOWING QUESTIONS ON MOMENTUM AND IMPULSE:

1. Impulse depends on both force and time. Give an example for each case:

a. a large force for a short time

b. a small force for a long time

c. a large force for a long time

d. a small force for a short time

2. Look at each situation below and explain the impulse and momentum changes. Also, include how changes in impulse could change the situation.

a. A professional golfer drives the golf ball far.

The more momentum the golf ball has, the farther it will go. A large impulse is needed to increase the balls momentum. The golfer should swing hard to increase the force of the impulse, and he should follow through. Following through gives more time for the force to act on the ball – increasing impulse and increasing the change in momentum. Both provide a large velocity to the ball which makes it go farthest.

b. A car brakes for a yellow light.

c. A baseball player catches a fastball thrown by the pitcher.

In order to reduce injury during a collision, the passenger must be slowed down safely. Car companies have designed many features of a car that increase the time it takes to slow passengers down. This reduces the size of the force to stop the passenger. 1. Use the pictures below and make a list of all the obvious 'safety' features in a car that help to increase the time of the collision so that a person is not injured when being stopped.

2. Make a list of anything else inside the car that you think was designed to help reduce injury in a collision.

3. What are “crumple zones,” and how do they help prevent injury in an accident?

4. Why is it important to slow the passengers down over a long period of time, versus quickly? (Think about riding a bike and hitting a brick wall versus hitting a chain-linked fence.)

ANSWER THE FOLLOWING PHYSICS REVIEW QUESTIONS:

1. A student is jogging around a football field that is 120 m long and 55.0 m wide. The student takes 120 seconds to jog around the field and return to his starting point. a. What is the average speed of the student? b. What is the average velocity of the student during this journey?

...... …………..

1 2 3 4

2. Using the position of the dots above to explain the velocity at points 1, 2, 3, and 4. (the velocity is constant, zero, decreasing, increasing …)

3. Briefly describe Newton’s 3 Laws. Give an example of each.

4. A car can accelerate from a stand still to 100 km/h [E] in 9.60 s. Calculate the average acceleration.

26 Mr. Storie 20F Science Student Package 3 – In Motion 5. Compare and contrast uniform and non-uniform motion, using the terms velocity and acceleration.

6. Use a picture and words to show how distance is different than displacement.

7. Explain the difference between vector and scalar and give 3 examples of each.

8. What does the “conservation of energy” mean in terms of a car crash?

9. What is instantaneous velocity?

10. Examine each Position-Time graph below and describe the following features:

i. direction and position of movement, ii. the sign and magnitude (increasing/decreasing/constant) of velocity iii. the sign of acceleration (positive/negative/zero) iv. Whether the object is uniform/non-uniform motion.

Time (s) Velocity (m/s) From the data in the table, describe the motion of the object. 0 + 10 1 + 9.0 2 + 8.0 What is the sign of the velocity? 3 + 7.0 4 + 6.0 What is the sign of the acceleration? 5 + 5.0

11. Car A, car B, and car C started at the same time and travelled on highway 401 from Kingston to Toronto. If car B reaches Toronto before car A and car C, then we can assume that (a) car A was travelling faster than car B and car C. (b) car B was travelling at the same speed as car A and car C. (c) car C was travelling at a greater speed than car B and car A. (d) car B was travelling faster than car A and car C.

12. Average speed can best be defined as (a) the speed at which an object is travelling at a particular instant; (b) an object travelling at the same speed over a period of time; (c) the total distance covered over the total time measured; (d) the rate of change in speed.

13. Instantaneous speed can be best defined as

26 Mr. Storie 20F Science Student Package 3 – In Motion (a) the speed at which an object is travelling at a particular instant;. (b) an object travelling at the same speed over a period of time; (c) the total distance covered over the total time measured; (d) the rate of change in speed.

14. Constant speed can be best defined as (a) the speed at which an object is travelling at a particular instant; (b) an object travelling at the same speed over a period of time; (c) the total distance covered over the total time measured; (d) the rate of change in speed.

15. The average speed and the instantaneous speed will be the same in which one of the following examples? (a) an average speed taken at the bottom of an incline as a skateboarder travels up the incline and the instantaneous speed taken when he reaches the top of the incline; (b) any point as a leaf is falling from a tree to the ground; (c) a car travelling at 100 km/h; (d) a car travelling at 100 km/h and then speeding up to 120 km/h.

Words you need to know the definitions for: Velocity Instantaneous Balanced Speed Rise Unbalanced Displacement Run Scalar Position Force Uniform Distance Newton Non-uniform Origin Inertia Instant / Interval Delta Acceleration Vector