Observe and describe the motion of everyday objects (MW2) Key Questions (MW2): How can you tell if an object is in motion? How can you tell if an object is speeding up or slowing down? How can you tell if an object is undergoing uniform motion? How does the choice of frame of reference influence the observation of motion and the motion itself? How can you use your own movements to represent uniform and non-uniform motion? Monday, October 22nd

Key Concepts (*Fill in Pink Sheet) Motion at a constant speed in a straight line is called uniform motion. All motion is measured relative to some frame of reference chosen by the observer Scientific knowledge is based on observation An operational definition of the physical sciences explains how to measure the quantity being defined

Introductory Brainstorming Examples of Motion: Give students handout MW2 observe and describe the motion of everyday objects

Examples of motion Videos of Motion Skateboards http://www.youtube.com/watch?v=9zAiiyhNAHs Skis http://www.youtube.com/watch?v=ebtGRvP3ILg Cars http://www.youtube.com/watch?v=Uiz7pfuCayM Kiteboarding http://www.youtube.com/watch?v=F_hgd3e0G3U Hockey http://www.youtube.com/watch?v=mJkEWfjUCOQ When viewing these videos, use your own words to describe the specific motion on the following slides

Description of Car Motion

Description of Skiing Motion

Description of Skateboard Motion

Description of Kiteboarding Motion

Description of Hockey

Words to Describe Motion Words that describe motion Forward Backward Fast Slow Up Down

Activity Time! In groups of 3, develop a 20 second skit showing as many types of motion as possible.

How can you tell an object is in motion? Words that describe motion Reference to something else Hearing a possible sound Seeing if it moves

What senses can we use to observe motion? How can you tell if an object is speeding up or slowing down? How quickly or slowly it moves The sound the object makes http://www.youtube.com/watch?v=h2eK8gazI_s What senses can we use to observe motion? Sight Hearing Touch Have students close their eyes and listen to the subway train getting closer Show it again so they can see it getting closer If we were at the subway station, we could feel the wind in the tunnel knowing it’s getting closer

Remarkable Feets Lab Tuesday, October 22nd

How can you tell if an object is undergoing uniform motion? Wednesday, October 22nd How can you tell if an object is undergoing uniform motion? Uniform Motion  Uniform motion describes an object travelling at a constant speed in one direction Non-Uniform Motion  when the direction or speed of motion changes

Characteristics of Uniform Motion 1) Distance Change in distance example: If you start at rest and travel 3.5m, what is your change in distance? Use: ∆ d = df – di df = 3.5m di = 0 m ∆ d = 3.5m – 0m ∆ d = 3.5m

Characteristics of Uniform Motion 2) Time A measure of duration Base unit is the second or “s” In Physics when we talk about time, we are really referring to a change in time Change in time = final time – initial time Or… ∆ t = tf - ti

Characteristics of Uniform Motion 2) Time Change in time example It took you 1.1s to travel your distance from rest Use ∆ t = tf – ti tf = 1.1s ti = 0s ∆ t = 1.1s – 0s ∆ t = 1.1s

Characteristics of Uniform Motion 3) Velocity A measure of a specific distance travelled in a specific amount of time Velocity = change in distance change in time Or… v = ∆ d ∆ t Base unit for velocity is meters per second or “m/s”

Characteristics of Uniform Motion 3) Velocity Example of velocity Based on the previous two examples, how fast were you travelling? Use v = ∆ d ∆ t ∆ d = 3.5m ∆ t = 1.1s v = 3.5m 1.1s v = 3.18 m/s

How does the choice of frame of reference influence the observation of motion and the motion of itself? Example: You are driving down the highway gazing out the side window while passing a semi. The truck driver speeds up while you are trying to pass so you are going nearly the same speed. Do you feel like you are moving? What about if you were driving down that same highway focusing on the center line instead of the truck beside you? Does your perception of motion change based on your frame of reference?