Concept Presentation- Motion

• Sheeladevi Ravindran

• Alexandra Kaklamanos

Motion

What are your thoughts on motion?

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

Overall Expectations

• B1. analyse technologies that apply concepts related to kinematics, and assess the technologies’ social and environmental impact;

• B2. investigate, in qualitative and quantitative terms, uniform and non-uniform linear motion, and solve related problems;

• B3. demonstrate an understanding of uniform and non-uniform linear motion, in one and two dimensions.

Motion

Prior Knowledge

•Grade 2 : Movement•Grade 3 : Forces causing movement•Grade 5 : Forces acting on structures and mechanisms•Grade 7 : Form and Function•Grade 8 : Systems in Action

Student Objectives/Learning Outcomes:

The student will:Identify forces that result in motionInvestigate and measure propulsion, gravity, and frictionDemonstrate and explain the effect of balanced and unbalanced forcesMeasure and graph movement of an object to calculate velocityApply forces and motion to a real-life experience through technology

Hook

Student Challenges

- Undifferentiated view- Position, Velocity & Acceleration- Speed vs. Velocity- Distance vs. Displacement- Velocity vs. Acceleration

- Creating and Understanding graphs

Common Misconceptions Time can be measured without knowing the beginning of the

interval.

The location of an object can be described by stating its distance

from a given point, ignoring direction.

The distance an object travels and its displacement are always

the same.

An object’s speed is the same as its velocity.

If an object is accelerating, then the object is speeding up.

An object’s acceleration cannot change direction.

Acceleration always occurs in the same direction as an object is

moving.

If an object has a speed of zero (even instantaneously), it has no

acceleration.

Lesson 1 – Frame of Reference

Lesson 2 – Position & displacement

Lesson 3 – Speed vs. Velocity (vectors)

Lesson 4 – Velocity

Lesson 5 – Acceleration

Lesson 6 – Circular Motion

Lab: Motion of a Motorized Cart

Purpose:To study the motion (position, displacement, velocity, and acceleration) of a motorized cart. To practice constructingposition vs. time and velocity vs. time graphs for a motion.

Equipment:constant velocity motorized cartmeter stick or metric tapeabout 2 meters of ticker tapegraph papermasking tapestopwatch or watch with a seconds handdata tablegrading rubric

Procedure:Setup:1.Fasten a 2-meter strip of ticker tape to your lab table with masking tape. 2.Place the motorized cart beside the tape, near one end. Mark the cart's starting position on the tape. 3.Adjust the speed of the cart so that it takes at least 30 seconds for the cart to move the length of the tape. Taking the Data:4.There are 3 jobs:

4. one person's job is to release the cart at the start of the run

5. a second person marks the position of the cart on the ticker tape

6. the third person watches the clock and calls out regular (5 second intervals might be convenient) time intervals.

5.You may want to make a couple of practice runs in order to get everyone coordinated, and remember that the tape has another side if you mess it up. When you are ready, release the cart and record its positions.

Analysis:Use a meter stick to measure each position of the cart (from the start). Record your data in the data table

Plot each position/time data pair on a position vs. time graph. Title the graph, select scale and title axes.

Draw the straight line (use a straight edge) that best fits your data points. DO NOT "connect the dots". Calculate and record the displacement of the cart during each time interval.

Calculate and record the average velocity (displacement/time) of the cart during each time interval. Plot each velocity/time data pair on a velocity vs. time graph. Title graph, select a scale, and title axes.

Draw the straight line (use a straight edge) that best fits your data points. DO NOT "connect the dots". Calculate the slope of the position vs. time and velocity vs. time graphs. Show your calculation.

Discussion Questions1.How do successive displacements of the cart compare? Why? 2.What is the slope of the position vs. time graph? What is the significance of this value? 3.How would the position vs. time graph be different if the cart had gone faster or slower? 4.What is the slope of the velocity vs. time graph? What is the significance of this value? 5.Was the velocity of the cart more-or-less constant during its motion? How do you know? 6.How would the velocity vs. time graph be different if the cart had gone faster or slower? 7.What was the acceleration of the cart during its motion? How do you know?

The good thing with the labs in this unit is that they do not require any specific safety procedures to be set in place BUT students should still be reminded that all equipment ought to be used as instructed, and that NO HORSEPLAY will be tolerated. Students who do not follow the rules will be asked to sit out and will get a failing mark on the specific assignment.

Assessment: Rubric Data for time and position are entered accurately and neatly.0-1 Calculations Displacements and average velocities are correct and readable.0-1 Sample Calculations Sample calculations for displacement and average velocity are complete, correct, and clearly shown.0-1 Graphs Position vs. time and velocity vs time graphs are accurate. The position and velocity axes are clearly and correctly labelled. A best-fit line has been drawn.0-3 Results & Conclusions Questions are answered clearly and correctly using literate, complete English sentences.0-4 Total 0-10

Possible Teaching StrategiesConstructivist teaching strategies :

- Pretest - Group Learning- Student debates- Demonstrations - Micro Computer Laboratory- Student/ Teacher initiated inquiries - Field trip

Other Teaching Ideas• Power Point:

http://www.batesville.k12.in.us/Physics/PhyNet/Mechanics/Kinematics/kine_in_a_nutshell.htm

• Other Labs: Accelerated Motion, Acceleration due to Gravity, Circular Motion

• Amusement Park Field Trip• Problems Solving – Numerical and Non-

numerical• Practical Application

Inquiry Activity

Please refer to the handout on « Moving Man – Simulation » and do the exercise online.

Moving man clicker QUIZ

Draw a velocity-time graph would best depict the following scenario?

A man starts at the origin, walks back slowly and steadily for 6 seconds. Then he stands still for 6 seconds, then walks forward steadily about twice as fast for 6 seconds

If the acceleration is Zero, the man must be standing still

• A. True

• B. False

• Velocity and acceleration are always the same sign (both positive or both negative).

A. True

• B. False

Math in Science

• Problem 1• In last week's Homecoming victory, Al Konfurance, the

star halfback of South's football team, broke a tackle at the line of scrimmage and darted upfield untouched. He averaged 9.8 m/s for an 80-yard (73 m) score. Determine the time for Al to run from the line of scrimmage to the end zone.

• Audio Guided Solution- http://www.physicsclassroom.com/calcpad/1dkin/prob4.

•

Math in Science

• Problem 2• The Lamborghini Murcielago can accelerate

from 0 to 27.8 m/s (100 km/hr or 62.2 mi/hr) in a time of 3.40 seconds. Determine the acceleration of this car in both m/s/s and mi/hr/s.

• Audio Guided Solution-http://www.physicsclassroom.com/calcpad/1dkin/prob7.cfm

Practical Applications

• Speed gun - for measuring the speed of a ball

• Accelometers used in video consoles• Photo radars – in cars• GPS

Students should research how some of these work and share with others.

Useful Websites

http://www.batesville.k12.in.us/Physics/PhyNet/Mechanics/Kinematics/kine_in_a_nutshell.htm

http://homepage.mac.com/vtalsma/misconcept.html

http://fi.edu/pieces/knox/automaton/motionlplans.htm

http://wings.avkids.com/Curriculums/Forces_Motion/

http://www.brighthub.com/education/k-12/articles/35418.aspx

Thank you !

Please copy and paste the link here to view a video on position, velocity and acceleration ! http://www.youtube.com/watch?v=O6Onfqt-Vzw