DO NOW: Write this down Textbooks covered by TUESDAY NEW for MP3: Online Textbook Code: www.classzone.com/eservices Username*:LMSGrade8 Password*: Lincoln8 *Case-sensitive Textbooks covered by TUESDAY NEW for MP3: Participation and Preparation Grade

Intro Activity The person sitting next to you is your partner. Choose an object in the room that is easy to see. Without pointing to, describing, or naming the object, give directions to the person next to you for finding it. Ask your partner to identify the object using your directions. If your partner does not correctly identify the object, try giving directions in a different way. Continue until your partner has identified the object.

Intro Activity Was your partner able to locate your object immediately? How many tries? If you had to change your directions, how did you change them? What kinds of information must you give another person when you are trying to describe a location?

Chapter 1.1 An object in motion changes position

Position Position: describes the location of an object Compare the location of an object with the location of another object or place.

Answer these questions

Frame of Reference (Reference Point) a stationary location or object to which you compare other locations or objects i.e. – you may be stationary as you sit in your seat, but you are moving 30 km/sec (≈19 mi/sec) relative to the Sun none are truly stationary relative to all others – what is not moving in one is moving in another How does frame of reference explain why people thought the Earth was in the center of all celestial bodies?

Measuring Distance The way you measure distance depends on information you want Straight-line distance Certain path Distance is measured in meters (m) Kilometers (km), Centimeters (cm)

Motion a change in position, or location of a place or object, over a certain amount of time Relative Motion: described by using a frame of reference, or reference point Relative Motion Simulation

Consider… A student sitting behind the driver of a moving bus. The bus passes another student waiting to cross the street. To the observer on the bus, is the driver changing position (in motion)? The street sign? To the observer on the sidewalk, is the driver changing position (in motion)? The street sign?

Suppose… You are in a train, and you cannot tell if you are stopped or moving. Outside the window, another train is slowly moving forward. Could you tell which situation is happening? Your train is stopped and the other train is moving slowly forward. The other train is stopped, and your train is moving slowly backward. Both trains are moving forward, with the other train moving a little faster. Your train is moving very slowly backward, and the other train is moving very slowly forward.

Answer? All four of these possibilities would look exactly the same to you! Your frame of reference depends on your own motion.