2. Describing Motion Chapter 1 - Section 1 Notes P: Identify the properties of objects that are in motion Q: How can an object be moving but not be in motion?

3. Definitions An object is in MOTION if its distance from another object is changing An object is in MOTION if its distance from another object is changing Reference point  a place or object used for comparison to determine if something is in motion Reference point  a place or object used for comparison to determine if something is in motion In other words…An object is IN MOTION when it changes position relative to a REFERENCE POINT. In other words…An object is IN MOTION when it changes position relative to a REFERENCE POINT.

4. Reference Points Good Reference Points = stationary objects Good Reference Points = stationary objects – (ex: tree, sign, building) Bad Reference Points  = any moving object Bad Reference Points  = any moving object – (ex: a moving car, a flying plane)

5. Types of Motion Straight line Straight line Projectile Projectile Circular Circular Vibrational Vibrational

6. Straight Line Motion Occurs when an object moves in a STRAIGHT LINE Occurs when an object moves in a STRAIGHT LINE – (ex: a moving car, plane or bicycle)

7. Projectile Motion Occurs when an object is thrown or projected Occurs when an object is thrown or projected – Moves in an arc/parabola Ex: a shooting cannon ball, arrow from a bow, or a baseball pitch Ex: a shooting cannon ball, arrow from a bow, or a baseball pitch

8. Circular Motion Occurs when an object spins/turns on its axis –E–E–E–Ex: Earth, a top, a Ferris wheel

9. Vibrational Motion Occurs when an object moves back and forth rapidly Occurs when an object moves back and forth rapidly – Ex: Sound waves, tuning forks, guitar strings, vocal chords, etc.

10. Relative Motion Whether or not an object is in motion depends on the reference point you choose! Whether or not an object is in motion depends on the reference point you choose! (See PAGE 8 in your textbook) *Are the skydivers in motion relative to each other? *Are they in motion relative to the airplane from which they jumped? *Are they in motion relative to the ground?

11. Consider this… Is it possible to be moving, Is it possible to be moving, but NOT be in motion?

12. LOL _________________________ Explain 1) Explain how an object can be moving but not relative motion be in motion. (Use the terms relative motion reference point and reference point in your explanation.) Compare and contrast 2) Compare and contrast the 4 types of motion. List 3) List 4 examples of objects that you 1 observe in motion today/tonight. (Find at least 1 each type examples of each type). What is the reference point in each example?

13. LOL( Challenge )__________________ Explain 1) Explain how an object can be moving but not relative motion be in motion. (Use the terms relative motion reference point and reference point in your explanation.) Compare and contrast 2) Compare and contrast the 4 types of motion. List 3) List 8 “real life” examples of objects that you 2 observe in motion today/tonight. (Find at least 2 each type examples of each type)