Translational Motion Circular Motion Projectile Motion

Motion Map Which direction is the object moving?

Tactics: Vector Addition Working in groups of 3, do two examples of vector addition -on your whiteboard, draw two random vectors, then add them graphically

Tactics: Vector Subtraction Working in groups of 3, do two examples of vector subraction -on your whiteboard, draw two random vectors, then add them graphically

The Displacement vector 1 2 r0 rr r1 Using vector subtraction and working on the whiteboards, show how you get this vector, Δr

Average Speed, Average Velocity To quantify an object’s fastness or slowness, we define a ratio as follows: Average speed does not include information about direction of motion. Average velocity does include direction. The average velocity of an object during a time interval Δt, in which the object undergoes a displacement Δr, is the vector

Motion Map Displacement vectors Velocity Vectors r0r0 r1r1 r2r2 r3r3 r4r4 v1tv1t v2tv2t v3tv3t v4tv4t v0tv0t

Motion Map Δt is the same between each position, so we can drop it Velocity, v, is proportional to displacement, Δr v1v1 v2v2 v3v3 v4v4 v0v0

Motion Diagrams with Velocity Vectors

Linear Acceleration Because velocity is a vector, it can change in two possible ways. 1.The magnitude can change, indicating a change in speed, or 2.The direction can change, indicating that the object has changed direction. We will concentrate for now on the first case, a change in speed.

Tactics: Finding the acceleration vector

Complete a motion diagram and find the acceleration for an object moving: Down an incline while speeding up Up an incline while slowing down

A particle undergoes acceleration while moving from point 1 to point 2. Which of the choices shows the velocity vector as the object moves away from point 2?

EXAMPLE 1.7 Interpreting a position graph

Tactics: Drawing a pictorial representation

General Problem-Solving Strategy

Draw a Pictorial Representation Jane slams on her brakes while driving 30 mph and skids to a halt in 60 feet. How long does it take her to come to a stop?

Graphical Representation Analyze the graph. Describe the motion by creating a pictorial representation. Time (s) Position (m)

Upcoming Assignments MasteringPhysics online HW due tonight by 11 pm Pre-class MasteringPhysics assignment due before class on Tuesday Pre-class MasteringPhysics assignment due before class on Thursday MasteringPhysics online HW due Thursday by 11 pm