Science starter: What graph would be best for this information? Day 3 1-28-11 Topic: Pre Unit 5 Objective: I can evaluate what I know about gravity and freely falling objects. Science starter: What graph would be best for this information? Pizza 50% Cheeseburgers 20% Tacos 15% Hotdogs 10% Other 5%

Find these words in your textbook and copy them into the vocabulary section of your notebook U5: FREE FALL & 2D MOTION Trajectory- Projectile- Free Fall- Circular motion- Perpendicular forces- Newton-

Answer the following questions: Read section 2.3 p.39-42 Answer the following questions: 1. Describe the motion of a freely falling object. Use the words speed, acceleration in your answer. 2. What is the difference between mass and weight? 3. If you drop a feather and a baseball in a place where there is no air (a vacuum), how will their motions compare? 4. Can an object have a speed of zero while it has an acceleration that is not zero? Explain. 5. An astronaut carries a rock from the moon to Earth. Is the rock’s mass the same on Earth as on the moon? Is its weight the same? Explain. 6. What is the direction of air resistance on a falling object?

First Five pages of Unit 5… First Five pages of Unit 5… *Start the top of each page with the corresponding Objective. 1 Describe and compare gravity as an attractive force among all objects(FM2.B.a/b) 2 Describe weight and free fall in terms of the force of a planet’s or moon’s gravity acting on a given mass(FM2.B.c/d) 3 Describe the force(s) that keep an object traveling in a circular path(FM2.E.a) 4 Describe the force(s) acting on a projectile on the Earth(FM2.E.b) 5 Predict the path of an object when the forces directing it change(FM2.E.c)

For future reference or vocab wall

Projectile- any object/body moving through space and affected only by gravity. EX: 1. ball 4. booger 2. bullet 5. marble 3. pencil If you launch or throw it…the “it” becomes a projectile.

Trajectory- the curved path a projectile follows.

Free Fall- the acceleration of a falling object under the sole influence of Earth’s gravitational force.

Circular motion- occurs when a force causes an object to curve in a full circle. EX: 1. planets orbiting the sun 2. a child on a merry-go-round 3. a basketball spinning on a fingertip

Perpendicular forces-

Newton-