Wednesday, 09/24/14 TEKs: P.4B:Analyze examples of uniform and accelerated motion By the end of today SWBAT: Understand Frame of Reference Essential Question: What is “frame of reference?” Topic: Frame of reference

You need: Physics Binder Wednesday, September 24, (Day 19)

 Do Now = 6 mins.  Objectives = 2 mins.  Frame of Reference = 12 mins.  Comic Instructions = 6 mins.  Comic Creativity! = 25 mins.

Key Question: How does your frame of reference affect what you observe? Objectives: Explain how physicists define a frame of reference. Set up a very brief experiment to analyze frames of reference from the perspective of different observers.

 In physics, the box containing the boy and girl is called a reference frame.  No experiment the boy or girl do inside the box can tell whether they are feeling the force of gravity or they are in a reference frame that is accelerating.

 Einstein’s theory of general relativity describes gravity in a very different way than does Newton’s law of universal gravitation.  Imagine a boy and girl who jump into a bottomless canyon, where there is no air friction.  On the way down, they throw a ball back and forth.

A paradox is a situation that does not seem to make sense.  A ball thrown from a moving train approaches you at the speed of the ball relative to the train plus the speed of the train relative to you.  The speed of light appears the same to all observers independent of their relative motion.

Conversation : Level = 2 [QUIET Convos] Help: Check with your group “Ask three, then me.” Activity: Focus on task at hand, Keep all group conversation ON TOPIC Movement: Sharpen Pencils, Pick up Supplies, Clean Desks & Lab Stations Participation: 100% INDIVIDUAL participation