Motion
Specific Concept: Projectile Motion
Concept Presentation
Nate Mohanlall, HS Physics OISE/UT
Instructor: Maria Price
1. Background Information
Gravity causes objects to accelerate downward. A projectile is an object moving in a vertical
plane, under the influence of the force of gravity. The factors that affect the trajectory of a
projectile motion are the initial velocity and the launch angle. The shape of the path of a
projectile is parabolic and information such as maximum height, time of flight and horizontal
range can be calculated.
A complete mathematical representation of Projectile Motion is tested in both the grade 11
and 12 curriculum. It is recommended that teachers focus on both qualitative and quantitative
understanding of the basic concepts and problem solving strategies. Teachers should also use
many projectile-related applications and technologies to explain the concepts.
2. Curriculum Placement
Elementary Curriculum
The concept of Projectile of Motion is explored ONLY in grade 2 in the elementary curriculum.
Grade 2 : Structures :Specific Expectations
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2.2 investigate and describe different kinds of movement (e.g., by observing how toys
and other everyday objects move)
3.2 identify ways in which the position of an object can be changed (e.g., by pushing,
by pulling, by dropping)
Secondary Curriculum
There is no mention of this kind of motion in grade 9 or 10 science curriculum. Projectile of
Motion is introduce in grade 11 (SPH3U) and taught in detailed in grade 12 physics course
(SPH4U).The big ideas of the kinematics and dynamics units in SPH3U and SPH4U are
summarized below. In the secondary curriculum students use mathematical representations to
solve problems involving Projectiles Motion as it applies to real world situation
Grade 11 Physics: Big Ideas
Kinematics
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Motion involves a change in the position of an object over time.
Motion can be described using mathematical relationships.
Many technologies that apply concepts related to kinematics have societal and
environmental implications.
Grade 12 Physics: Big Ideas
Dynamics
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Forces affect motion in predictable and quantifiable ways.
Forces acting on an object will determine the motion of that object.
Many technologies that utilize the principles of dynamics have societal and
environmental implications.
3. Misconceptions
Students develop personal “theories of motion” by generalising the ideas they acquire from
observation of objects in everyday situations (Keeports, 2000)
Misconception # 1: Heavier objects fall faster.
Strategies use to address misconception:
Demonstration:
 Use two balls with different masses and release from same height for tactile and visual
learners
 Use Applets to demonstrate with explanation for visual and auditory learners.
Explanation:
By viewing the applets, demo and explanation students can conclude that heavier objects hit the
ground at the same time as lighter ones.(Air resistance is ignore)
Misconception # 2: If one object is dropped from a specific point and another is projected
forward from the same point, then the projected object will take longer to reach the ground.
Strategies use to address misconception:
Demonstration:
 Drop one object from a specific point and another is projected forward from the same
point for tactile and visual learners and while auditory learners listen for the number of
sounds they hear - one or two - when the object hit the ground.
 Use Applets to demonstrate with explanation for all learners.
Explanation:
By viewing the applets and doing the demo students can conclude that both objects hit the
ground at the same time. (Air resistance is ignore)
Misconceptions # 3 Parabolic Motion: Showing the parabolic nature of projectiles leads the
student to believe they are quite different from linear falling or horizontal motion
Strategies use to address misconception:
Demonstration:
 Use Applets to demonstrate for visual learners.
 Tactile learners can use chalkboard to sketch
Explanation:
An easy way to deal with this is to plot the motion of a freely falling object and a horizontally
moving object on the same graph. When the intersection points at the same time, are
connected, the result is a parabola
Misconceptions # 4 Parabolic Motion: At the peak of its trajectory, the velocity of a
projectile is always momentarily zero. The acceleration of the object is also zero, at the peak.
Strategies use to address misconception:
Demonstration:
 use chalkboard to sketch parabolic path to show all learners
Explanation:
Have students look at the horizontal and vertical velocity vectors throughout parabolic
flight. Demonstrate that the velocity is not zero as there must be some horizontal motion
still (it doesn’t stop in midair).If you throw an object in the air, it stops briefly (speed is zero)
but acceleration is not zero (gravity doesn’t “lock-off”). Its role is to change the direction of
the velocity vector.
Misconception # 5:
Students believe that the greater the angle of projection, the greater the horizontal
distance travelled by a projectile.
Strategies use to address misconception:
Demonstration:
 Use Applets to demonstrate for visual learners.
 Tactile learners can use chalkboard to sketch projectile path
Explanation:
Seeing the animation students will quickly realize that the maximum horizontal range possible is
at 45 degrees and as the angle increase or deceases the range decreases.
4. Lesson Sequence
Description of Activity
Teaching/Learning
Strategies
-Group work
-Independent
work(Graphic
organizer)
-Demo Projectile
Motion(to reinforce
concept quiz)
Expectations
Addressed
Learning Styles
Assessment
A1.5
A1.10
A1.12
Kinesthetic/Tactile
Visual
Linguistic
Intrapersonal
Diagnostic
1. Discuss how objects release from
the same height and projected
horizontally and with different
masses hit the ground the same
time.
2. Parabolic motion and angle of
projection
3. Comparing Horizontal Range
:Using formula to verify maximum
possible range using different
angles and a fixed initial velocity
-Animation
B2.1
B2.2
Visual
Auditory
Kinesthetic/Tactile
Interpersonal
Formative
Day 4:
-Direct Instruction
student involved
Day 1:
1. Diagnostic lab :Projectile
motion
2. Vocabulary : Complete graphic
organizer using textbook
B1.1
B2.1
-
observe students as they complete graphic
organizer and perform lab
Concept quiz
Day 2 and 3:
1. Problem Solving
-Analyzing more complex projectile
motion
-Analyzing the motion of objects
projected horizontally
-Class work
-Investigation
Group work
Textbook
-Gizmos
-Independent work
Parallel
Questions(DI)
-PhysicsTool box
B1.2
B2.1
B2.2
B2.3
-
Checking for understanding
Questioning of students based on their
mathematical knowledge
- Solve for maximum range using formula
- Complete questions using Gizmos worksheet
-concept quiz
Formative
Kinesthetic
Visual
Auditory
-
Concept circle
Checking on students problem solving skills
mathematical analysis of projectile motion
- assignment (Parallel Questioning, DI)
Summative
-
Quiz, Test
5. Advance Preparation/Materials needed
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Prepare Power Point Presentation and search for applets/ animations and other
internet resources that will be used to target all learners.
Gathering of materials to illustrate demo in the classroom
Prepare Parallel Questions(DI)
Prepare test, quiz (concept) and assignment
6. Applications and Societal Implications
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Sports e.g. base ball is a projectile game-the pitcher throws a ball at the batter,
who hits it to an open area in the field. The outfielder catches the ball and
throws it to second base. The runner is out. All aspects of this sequence involve
projectile motion
Weapons-the most complex form of projectile widely known in modern life is the
rocket or missile. Missiles are unmanned vehicles, most often used in warfare to
direct some form of explosive toward an enemy.
Forensic -Ballistics (gunfire pattern undergoes projectile motion) is a significant
part of police science for the purpose of crime-solving, because it allows lawenforcement investigators to determine when, where, and how a firearm was
used.
Forest Fire-water hose and water bomber uses projectile motion to out forest
f ir e .
Circus/fireworks- at a circus human cannon and fireworks undergoes projectile
motion
Drop food in disaster areas with airplane- the package release from a moving
airplane will trace the path of a projectile.
7. Assessment and Evaluation
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Assignment- formative and ongoing
Quiz-short quizzes on concept not calculation
Test- problem solving testing mathematical representation and algebraic
manipulations and concepts
Lab- formative and summative and ongoing
8. Essential Expectations
Grade 12
A1. Scientific Investigation Skills
A1.5 conduct inquiries, controlling relevant variables, adapting or extending procedures as
required, and using appropriate materials and equipment safely, accurately, and effectively, to
collect observations and data
A1.10 draw conclusions based on inquiry results and research findings, and justify their
conclusions with reference to scientific knowledge
A1.12 use appropriate numeric (e.g., SI and imperial units), symbolic, and graphic modes
of representation (e.g., vector diagrams, free-body diagrams, vector components, and
Algebraic equations)
B1. Relating Science to Technology, Society, and the Environment
B1.1 analyse, on the basis of research, a technology that applies concepts related to kinematics
(e.g., devices used to measure speed in sports; rocket accelerators; motion-detecting sensors for
security systems; speedometers in automobiles) [IP, PR, AI, C]
B2. Developing Skills of Investigation and Communication
B2.1 use appropriate terminology related to kinematics, including, but not limited to: time,
distance, position, displacement, speed, velocity, and acceleration [C]
B2.6 plan and conduct an inquiry into the motion of objects in one dimension, using vector
diagrams and uniform acceleration equations [IP, PR, C]
B2.8 use kinematic equations to solve problems related to the horizontal and vertical
components of the motion of a projectile (e.g., a cannon ball shot horizontally off a cliff, a ball
rolling off a table, a golf ball launched at a 45º angle to the horizontal) [AI, C]
9. Annotated References
On-Line Resources
http://www.edu.gov.on.ca/eng/curriculum/elementary/scientec18currb.pdf.
http://www.edu.gov.on.ca/eng/curriculum/secondary/2009science11_12.pdf
http://www.explorelearning.com/index.cfm?method=cResource.dspDetail&ResourceID=523
http://www.physicsclassroom.com/mmedia/vectors/bds.gif
http://www.lon-capa.org/~mmp/kap3/cd060.htm
http://www.walter-fendt.de/ph14e/projectile.htm
http://www.falstad.com/mathphysics.html
http://www.physicsclassroom.com/mmedia/vectors/mzi.cfm
Print Resources
1. Hirsch, Alan J., et al, Physics 12, Toronto, ON, Nelson Thomson Canada Ltd., , 2003,
Dynamics
2. Keeports, D. (2000). Addressing physical intuition-a first day event. The Physics
Teacher,38, 318-319.