© 2010 Pearson Education, Inc.

Week 4 Day 1: Topics

Slide 1-7

Particle Model

General Motion Model

Constant Velocity Model

Representations of Motion

• Motion Graphs

• Motion Diagrams

•Velocity graph to Position

•Acceleration

© 2010 Pearson Education, Inc.

General Motion and Constant Velocity Motion

• General Motion Model - Definitions

• Position

• Distance

• Displacement

• Average Speed

• Average Velocity

• Instantaneous Speed

• Instantaneous Velocity

• Constant v motion -Representations of motion

• Motion Diagram

• X vs. t graphs

• Vx vs, t graphs

• Describing motion in words

x = v*Delta t

• Particle Model

© 2010 Pearson Education, Inc.

Acceleration

Acceleration is:

• The rate of change of velocity

• The slope of a velocity-versus-time graph

Slide 2-26

© 2010 Pearson Education, Inc.

Particle Motion:

Slide 1-7

The picture above is made with a stroboscope (a light that flashes at regular time intervals) made at two frames of film per second, of a ball rolling along a track. The track has a 3.0-m-long sticky section.

a.Make a position-versus-time graph for the ball. Because you have data only at certain instants of time, your graph should consist of dots that are not connected together.

b.What is the change in the ball’s position from t = 0 s to t = 1.0 s?

c. What is the change in the ball’s position from t = 2.0 s to t = 4.0 s?

d. What is the ball’s velocity before reaching the sticky section?

e. What is the ball’s velocity after passing the sticky section?

f. Determine the ball’s acceleration on the sticky section of the track.

© 2010 Pearson Education, Inc. Slide 2-34

Where’s the train?

A train is moving at a steady 30 m/s. At t = 0, the engine passes a signal light at x = 0. Without using any formulas, find the engine's position at t = 1s, 2s, and 3s.

Express your reasoning in words.

© 2010 Pearson Education, Inc. Slide 2-34

Where’s the train?

A train is moving at a steady 30 m/s. At t = 0, the engine passes a signal light at x = 0. Without using any formulas, find the engine's position at t = 1s, 2s, and 3s.

Express your reasoning in words.

EQUATION FROM GRAPH

EQUATION FROM AREA

© 2010 Pearson Education, Inc. Slide 2-34

Where’s the train?

A train is moving at a steady 30 m/s. At t = 0, the engine passes a signal light at x = 0. Without using any formulas, find the engine's position at t = 1s, 2s, and 3s.

Express your reasoning in words.

EQUATION FROM GRAPH

EQUATION FROM AREA

Suppose instead of starting at x = 0, we start at x = 50 m?

© 2010 Pearson Education, Inc.

A graph of velocity versus time for a hockey puck shot into a goal appears like so:

Which of the following position graphs matches the above velocity graph?

Checking Understanding

A. B. C. D.

Slide 2-21